A sniper's laser target aimed at Boston Marathon suspect Dzhokhar Tsarnaev's head is seen in this photo by Massachusetts State Police Sgt. Sean Murphy and posted by <a href="http://www.bostonmagazine.com/news/blog/2013/07/18/tsarnaev/ " target="external">Boston Magazine.</a>

The red circle highlights the pressure cooker bomb that was used just moments after this photo was taken. The use of this explosive created an enormous cloud of smoke that covered the entire street. While the street was still cloudy with smoke one of the brothers started running down the street towards the officers, while still engaging them in gunshots.

The red circle highlights where one of the brothers was taken down and still laying in the street. The black SUV proceeded to accelerate towards the officers and drove in between the two cars at the top of the picture. The SUV side swiped both cars taking out doors and windows and ultimately broke through the vehicle barricade and continued driving west on Laurel St.

At the bottom of this image is the blast mark from the pressure cooker bomb that exploded in the middle of the street. At the top of the image, the bright light is a bomb detecting robot that was moving toward the blast mark.

The bomb squad had finally inspected the entire vehicle and all the backpacks beside it and have cleared the area.

As soon as the black SUV had left the street officers rushed toward the green sedan and the spot of the shooting. As soon as officers got to the vehicle they started alerting all others on scene that there were "IEDs" on the street and for everyone examining the scene to clear the entire street.

Mass State Police posted this photo from State Police Air Wing on Watertown manhunt on their twitter page, April 20, 2013.

Mass State Police posted this photo from State Police Air Wing on Watertown manhunt on their twitter page, April 20, 2013.

Mass State Police posted this photo from State Police Air Wing on Watertown manhunt on their twitter page, April 20, 2013.

Mass State Police posted this photo from State Police Air Wing on Watertown manhunt on their twitter page, April 20, 2013.

Mass State Police posted this photo from State Police Air Wing on Watertown manhunt on their twitter page, April 20, 2013.

This still frame from video shows Boston Marathon bombing suspect Dzhokhar Tsarnaev visible through an ambulance after he was captured in Watertown, Mass., April 19, 2013.

This picture taken by WMUR anchor, Jenan Mackin, shows bombing suspect Dzhokar Tsarnaev critically injured in the back of an ambulance, April 19, 2013.

President Barack Obama speaks in the Brady Press Briefing at the White House in Washington, April 19, 2013, regarding the Boston Marathon bombing.

A gathering applaud as police leave the scene of the arrest of a suspect of the Boston Marathon bombings in Watertown, Mass., April 19, 2013.

Police SWAT team member smile as they leave the scene of the arrest of a suspect of the Boston Marathon bombings in Watertown, Mass., April 19, 2013.

A SWAT officer raises his fist in Watertown, Mass., April 19, 2013, after the manhunt for the second of two suspects in the Boston Marathon bombing was captured.

Crowds cheer on police officers as they exit the scene of where Dzhokhar Tsarnaev was hiding, April 19, 2013.

The FBI immediately updated their wanted poster after Dzhokar Tsarnaev was apprehended by police in Watertown, Mass., April 19, 2013.

Police officers guard the entrance to Franklin street where Dzhokhar Tsarnaev was hiding in a boat, April 19, 2013, in Watertown, Mass.

A boat seen on Bing maps is where law enforcement personnel are focusing their attention. Authorities believe the second shooter might be hiding in this boat.

Law enforcement search for the suspect in the Boston Marathon bombings, April 19, 2013, in Watertown, Mass.

Law enforcement approach an area reportedly where a suspect is hiding on April 19, 2013 in Watertown, Mass.

Law enforcement personnel enter blocked-off perimeter of where the bombing suspect Dzhokhar Tsarnaev is believed to be hiding, April 19, 2013.

FBI agents search the New Jersey home of the Boston bombing suspects' sister, Ailina Tsarnaev.

Police action at 17 Willow Avenue during the ongoing manhunt for a suspect in the terrorist bombing of the 117th Boston Marathon. Watertown is on lockdown following a chase and shootout in the area last night.

Maret Tsarnaeva, an aunt of the two suspects in the Boston Marathon bombing, speaks to journalists in the lobby of her apartment building in Toronto on April 19, 2013.

The father of Boston bomb suspects, Anzor Tsaraev, reacts as he talks to the media about his sons, in his home in the Russian city of Makhachkala, April 19, 2013.

Tamerlan Tsarnaev practices boxing at the Wai Kru Mixed Martial Arts center in April 2009 in Boston. Tamerlan, 26, was killed after he and his brother exchanged gunfire with police officers early on April 19, 2013 in Watertown, Mass. Multiple explosive devices were detonated during the firefight.

Tamerlan Tsarnaev practices boxing at the Wai Kru Mixed Martial Arts center in April 2009 in Boston. Tamerlan, 26, was killed after he and his brother exchanged gunfire with police officers early on April 19, 2013 in Watertown, Mass. Multiple explosive devices were detonated during the firefight.

Tamerlan Tsarnaev practices boxing at the Wai Kru Mixed Martial Arts center in April 2009 in Boston. Tamerlan, 26, was killed after he and his brother exchanged gunfire with police officers early on April 19, 2013 in Watertown, Mass. Multiple explosive devices were detonated during the firefight.

Tamerlan Tsarnaev practices boxing at the Wai Kru Mixed Martial Arts center in April 2009 in Boston. Tamerlan, 26, was killed after he and his brother exchanged gunfire with police officers early on April 19, 2013 in Watertown, Mass. Multiple explosive devices were detonated during the firefight.

Dzhokhar Tsarnaev wrestles during the Framingham Tournament, Dec. 2010. Dzhokhar remains at large and is the subject of a manhunt, police said April 19, 2013.

A sign calling for citizens of Boston to "Shelter in Place" is shown on I-93 in Boston, April 18, 2013.

Ruslan Tsarni, the uncle of the Boston Marathon bombing suspect, speaks with the media outside his home in Montgomery Village, Md., April, 19, 2013.

A police officer evacuates a shoeless man holding a child as members of law enforcement conduct a search for a suspect in the Boston Marathon bombings, April 19, 2013, in Watertown, Mass.

Authorities tow away a Mercedes-Benz SUV that one of the Boston bomber suspects carjacked at a gas station, April 19, 2013.

MIT Police Officer Sean Collier, 26, of Somerville, Mass., was shot to death, April 18, 2013 on the school campus in Cambridge, Mass. Authorities said surveillance tape recorded late Thursday showed one of the Boston Marathon bombing suspects during a robbery of a nearby convenience store before Collier was shot to death while responding to a report of a disturbance.

Massachusetts Bay Transportation Authority transit police officer Richard Donohue, 33, who was critically injured in an early morning shootout, April 19, 2013, with the two suspects in the Boston Marathon bombings.

Dzhokhar Tsarnaev has been on the run, described as "armed and dangerous" and suspected of the Boston Marathon bombing. His brother, Tamerlan, was killed during a violent police chase. The two ethnic Chechen brothers came from Dagestan, a Russian republic bordering the province of Chechnya.

Tamerlan Tsarnaev, left, accepts the trophy for winning the 2010 New England Golden Gloves Championship in Lowell from Dr. Joseph Downes.

NPR host Robin Young tweeted this photo of her nephew with Dzhokhar Tsarnaev, a suspect in the Boston Marathon bombings with the caption, "My beloved nephew on right, djohar tsarnaev on left, happy cambridge Rindge and Latin grads.heartbreaking."

Cambridge Boston is empty, seen here in this Twitter photo posted by BikeSafeBoston with the words, "Locked down in Central Square, #Cambridge," April 19, 2013.

Police in tactical gear surround an apartment building while looking for a suspect in the Boston Marathon bombings in Watertown, Mass., April 19, 2013. All residents of Boston were ordered to stay in their homes as the search for the surviving suspect in the marathon bombings continued after a long night of violence that left another suspect dead.

Police presence grows in the neighborhoods of Watertown, Mass., April 19, 2013, as a massive search involving hundreds of heavily armed law enforcement officials continues for one of two suspects in the Boston Marathon bombing.

Police in tactical gear arrive on an armored police vehicle as they surround an apartment building while looking for a suspect in the Boston Marathon bombings in Watertown, Mass., April 19, 2013.

Authorities say Dzhokhar A. Tsarnaev is still at large after he and another suspect, both identified to The Associated Press as coming from the Russian region near Chechnya, killed an MIT police officer, injured a transit officer in a firefight and threw explosive devices at police during their getaway attempt, April 19, 2013.

This April 15, 2013 photo provided by Bob Leonard shows third from left, Tamerlan Tsarnaev, who was dubbed Suspect No. 1 and second from left, Dzhokhar A. Tsarnaev, who was dubbed Suspect No. 2 in the Boston Marathon bombings by law enforcement. This image was taken approximately 10-20 minutes before the blast.

This surveillance photo released via Twitter, April 19, 2013 by the Boston Police Department shows a suspect entering a convenience store that police are pursuing in Watertown, Mass. Police say he is one of two suspects in the fatal shooting of an MIT police officer and tied to the Boston Marathon bombing.

The two suspects in the Boston Marathon bombing walk near the marathon finish line, April 15, 2013 in Boston, Mass. The twin bombings at the 116-year-old Boston race resulted in the deaths of three people with more than 170 others injured.

Swat team members in Boston continue the manhunt for the Boston Marathon suspect, April 19, 2013.

Police with guns drawn search for a suspect, April 19, 2013 in Watertown, Mass. Earlier, a Massachusetts Institute of Technology campus police officer was shot and killed late Thursday night at the school's campus in Cambridge.

Police officers aim their weapons, April 19, 2013, in Watertown, Mass. A tense night of police activity that left a university officer dead on campus just days after the Boston Marathon bombings and amid a hunt for two suspects caused officers to converge on a neighborhood outside Boston, where residents heard gunfire and explosions.

Police work a crime scene, April 19, 2013, in Watertown, Mass. A tense night of police activity that left a university officer dead on campus just days after the Boston Marathon bombings and amid a hunt for two suspects caused officers to converge on a neighborhood outside Boston, where residents heard gunfire and explosions.

Officials brief the media on a standoff in Watertown, Mass., April 19, 2013. Authorities say one of two suspects in the Boston Marathon bombing is dead and a massive manhunt is underway for another in the Boston suburb of Watertown early Friday morning April 19, 2013.

Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device.

A screen grab shows what appears to be Martin Richard, circled left, the 8-year-old victim of the Boston Marathon bombings and one of the suspects, circled right, minutes before the bomb went off, April 15, 2013.

Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device.

Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device.

Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device. The photos were produced by the Joint Terrorism Task Force of Boston.

Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device.

Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device.

Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device.

Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device.

Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device.

Boston Marathon bomb scene pictures taken by investigators show the remains of an explosive device. <a href="http://abcnews.go.com/US/slideshow/boston-marathon-explosions-finish-line-18960444">More Photos</a>