A federal grand jury has issued a 30-count indictment against the surviving Boston Marathon bombing suspect, Dzhokhar Tsarnaev, accusing him of using weapons of mass destruction, killing four people, and contributing to his own brother's death.
The 74-page indictment details for the first time the role jihadist material online allegedly played in radicalizing Tsarnaev and his older brother Tamerlan and offers new insight into how they purportedly prepared for the attack -- beginning as early as February 2013.
"[T]oday's action proves our unyielding resolve to hold accountable -- to the fullest extent of the law -- anyone who would threaten the American people or attempt to terrorize our great cities," Attorney General Eric Holder said in a statement.
According to the indictment, Dzhokhar Tsarnaev downloaded a significant amount of jihadist material from the Internet, including a book about "disbelievers" with a foreword by radical cleric Anwar al-Awlaki. In addition, he downloaded Volume One of the Al Qaeda-produced magazine "Inspire," which offered detailed instructions for building bombs with pressure cookers, shrapnel and explosive powder from fireworks, the indictment said.
DOWNLOAD: U.S. vs. Dzhokhar Tsarnaev (PDF)
On March 20, nearly a month before the attack on the Boston Marathon, the Tsarnaev brothers visited a firing range in Manchester, N.H., where they rented 9mm handguns and "engaged in target practice" for about one hour, according to the indictment.
Then, on April 15, the brothers allegedly carried backpacks containing pressure cookers packed with explosives, BBs and nails to the site of the Boston marathon, according to previously-filed court documents and law enforcement sources.
When the devices exploded just seconds apart, three people were killed, including an 8-year-old boy, and more than 260 others were injured.
"Today's charges reflect the serious and violent nature of the events that occurred on April 15th and the tragic series of events that followed," the U.S. Attorney for the District of Massachusetts, Carmen Ortiz, said in a statement. "The defendant's alleged conduct forever changed lives. The victims, their families and this community have shown extraordinary strength and resilience in the face of this senseless violence."
In addition to the federal indictment announced Thursday, state officials in Massachusetts announced their own indictment against Tsarnaev, charging him with more than a dozen state offenses, including the murder of the MIT officer, Sean Collier.
New Details: When Dzhokhar Allegedly Ran Over His Brother
The indictment announced Thursday also offered new details about the hunt for the Boston bombing suspects.
Hours after the FBI released images of the suspects on April 18, the brothers "armed themselves with five [homemade bombs], a Ruger P95 9mm semiautomatic handgun, ammunition for the Ruger, a machete, and a hunting knife," according to the indictment. The brothers then allegedly drove in their Honda Civic to the Massachusetts Institute of Technology in Cambridge, Mass., where they came upon MIT officer Sean Collier and killed him "by shooting him in the head at close range."
Hours later, after carjacking a Mercedes from someone else and driving to Watertown, Mass., authorities caught up with the pair. The brothers allegedly began firing and threw four of the homemade bombs at them. At one point the police got so close that they engaged in hand-to-hand combat with the older Tsarnaev.