Fox Lake Police
Police officers salute at a vigil for slain police Lt. Charles Joseph Gliniewicz in Fox Lake, Illinois, on Sept. 2, 2015. Reuters/Jim Young

Police in the suburban Illinois community where a police officer was shot and killed this week said they might soon reveal "significant" evidence in the case, including footage from a home security video system in the area of the shooting. The video could help authorities determine who was responsible for the Tuesday morning death of Fox Lake, Illinois, police Lt. Charles Joseph Gliniewicz, an official told CNN Thursday.

Gliniewicz, a 32-year veteran of the force who was nearing retirement, had indicated that he’d encountered two white men and a black man shortly before the shooting, but there had been no other visual evidence to support that description of the suspects. A resident in Fox Lake turned over his home surveillance video after telling police that he saw three people in the area, said George Filenko, commander of the Lake County, Illinois major crime task force investigating the shooting.

Local investigators lacked the proper equipment to review the man’s surveillance footage, so they sent it to a nearby office of the U.S. Department of Homeland Security, Filenko told CNN Thursday. "Again, we don't believe in coincidences. However, we still don't know, and I can't verify exactly whether this video is relevant to the case," he said. "But at this point it's probably one of the most significant ones we've recovered."

In addition to the home security video, authorities said they also have a video taken by a truck driver who had a camera in his vehicle and was in the area of the shooting Tuesday. The incident has rocked the community and enraged police groups around the country, who have said anti-police protests encouraged by the Black Lives Matter movement have put police officers at risk.

Twenty-three police officers have been killed by gunfire so far this year -- three of them targeted because they were police officers, according to the national Fraternal Order of Police, an advocacy group. The Fox Lake shooting came less than a week after an attack in Texas that left a suburban Houston sheriff's deputy dead last Friday.

The National Organization of Black Law Enforcement Executives condemned the shootings in a statement released Friday. "All of our nation's law enforcement officers are painfully aware of the dangers that they can face as they conduct their work,” Gregory Thomas, NOBLE's national president, said in the statement. “We ask that all citizens pause to consider the great work that the vast majority of law enforcement officers do in protecting and serving our communities, all while facing the dangers of their profession."

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