The sister of Officer Luis Huesca is pleading with the public to help investigators identify and catch a suspect who allegedly gunned him down.

Police have issued an arrest warrant for a 22-year-old in connection with the shooting of the 30-year-old officer and have increased the reward for information leading to the arrest of the shooter.

"I feel like the community needs to show up for him," the sister said.

The famous rat-sized dent in a Chicago sidewalk, dubbed the "rat hole," was removed and preserved by city officials Wednesday.

The famous rat-sized dent in a Chicago sidewalk, dubbed the "rat hole," was removed and preserved by city officials Wednesday.

Hoping for a break in the homicide investigation of Chicago police Officer Luis Huesca, investigators have released security video of a person of interest.

A Chicago police officer, who was gunned down Sunday outside his home after returning from his shift, had his gun taken from him as well as his car in the attack.

Police say the video shows a person of interest in the killing of Officer Luis Huesca.

Police are searching for a suspect and a motive in the shooting death of an off-duty Chicago police officer. Authorities say the officer was gunned down as he headed home from his shift.

Police said the officer was in his uniform, but with a jacket over it at the time he was shot.

Seven people lost their lives after multiple shootings during a violent weekend in Chicago including one child killed after gunfire erupted at a family gathering.

A child was killed and at least 10 other people were injured, including a 1-year-old and an 9-year-old, when gunfire broke out in Chicago, according to police.

The Chicago Civilian Office of Police Accountability has released bodycam footage of a police shooting that occurred last month in West Garfield Park.

The estimate from Johns Hopkins Bloomberg School of Public Health and the Stanford University School of Medicine was published in the journal JAMA Pediatrics.

At least eight people were hurt, including an infant, in the blaze, firefighters said.

Founded by a former NFL player, the Male Mogul Initiative teaches leadership and provides a path to success for young men from under-resourced Chicago neighborhoods.

A Chicago man — dressed in his swim trunks — braved the sub-zero wind chill to take a leisurely stroll on the pancake ice covering Lake Michigan.

A Chicago commuter train collided with rail equipment, injuring at least 19 people, officials said.

Five people were hospitalized after the tent that was set up for an event outside Chicago collapsed, investigators said.

ABC News’ Alex Perez is in Chicago where heat has forced schools to change schedules and cancel in-person classes.

Thousands of rubber ducks raced down the Chicago River and floated to the finish line in the annual Duck Derby, a charity event supporting Special Olympics Illinois.

Michael Goodman, 43, has been charged with first-degree murder in connection the death of Serabi Medina, Chicago police officials said in a statement.

Plus, a woman in Maine recovers after fighting off a black bear in her backyard.

More than 70 people were shot, 13 fatally, in Chicago over the holiday weekend, including a father of four who was gunned down at a Father's Day park gathering.

More than 50 people were shot, 11 fatally, over a violent Memorial Day weekend in Chicago, police said.

Community members gathered outside the district police station asking for the public's help.

At least nine incidents have occurred in Lawndale since early March.

Lightfoot and Adams said Texas intends to begin busing migrants to major cities starting today.

Mayor-elect Brandon Johnson talks about his goals for the city and its residents.

Brandon Johnson told GMA3 he is committed to addressing "root causes."

A 25-year veteran firefighter collapsed on the 11th floor and was unable to be revived.

Residents of Little Village are demanding answers from authorities on the incidents.

Two women were found dead in recent weeks, and a teenager is now missing in Chicago's Little Village neighborhood, community leaders said.

All four members of a firefighter's family were killed in a housefire on Chicago's northwest side.

A Chicago police officer was shot and killed Wednesday while responding to a call about a person with a firearm, according to the Chicago Police Department.

Officer Andres Vasquez-Lasso was on the force for five years.

The officer was responding to a call about a person with a firearm, police said.

Former Chicago Public Schools CEO Paul Vallas and Cook County Commissioner Brandon Johnson both advanced to the runoff election, to be held on April 4.

Flames poured from the windows of the 15th floor, where the fire began, before wind spread the blaze to the 24th floor.

Chicago leaning into Boaty McBoatface controversy, allowing residents to vote to name six of Chicago’s snow plows.

The worker died at the hospital after he was trapped under several feet of debris for 45 minutes, authorities said.

Peter Salvino, a Ph.D. candidate in Northwestern's interdepartmental neuroscience program, was reported missing on Sunday by his family.

Students at a Chicago high school are planning a classroom walkout Monday afternoon to protest gun violence just days after a shooting near their campus.

Chicago street artist, founder of "Poetry by Boots" Kimberly "Boots" Brown, advocates to spread uplifting messages on all 50 state sidewalks to help others suffering from heartache and mental health.

The family is alleging workers failed to properly secure their child to the wall with a harness and rope.

A 3-year-old was among the injured.

Five men were shot, three fatally, early Sunday when gunfire erupted at a Chicago intersection taken over by a drag-racing caravan of more than 100 cars, police said.

A 13-year-old boy was among six people killed in unrelated shootings across Chicago over weekend that also left 23 people with bullet wounds, according to police.

The attempted kidnapping caught on camera in Chicago’s West Loop showed a woman nearly abducted in broad daylight.

At least eight people were injured in an explosion at a residential building in Chicago and the cause is still under investigation.