Dallas Mass Shooting Is Deadliest Day for Law Enforcement Since 9/11

The attack was one of the deadliest for law enforcement in 50 years.

The Dallas Police Department has confirmed that four of its officers have died, and Dallas Area Rapid Transit (DART) has confirmed that one of its officers also died. DART identified him as Officer Brent Thompson, 43. He was the first DART officer to be killed in the line of duty since the agency's formation.

Other deadly incidents for law enforcement include a sniper attack in New Orleans in the 1970s.

Over eight days in 1972 and 1973, five officers were killed by a sniper in New Orleans. The gunman was a member of the Black Panthers. The shootings started on New Year's Eve and ended when the suspect was shot and killed by police, who used a Marine helicopter to fly over a hotel where he had holed up and fired at him.

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