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

— -- The mass shooting in Dallas that left five officers dead and six others wounded was the deadliest attack on law enforcement since 9/11, according to statistics from the National Law Enforcement Officers Memorial Fund.

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.

The deadliest day for U.S. law enforcement was 9/11, when 71 officers died while responding to the terrorist attacks on the World Trade Center in lower Manhattan, including 37 members of the Port Authority of New York and New Jersey Police Department — the largest loss of law enforcement personnel by a single agency in U.S. history, according to the fund.

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.

Eight federal officers were killed in April 1995, when domestic terrorists, led by Timothy McVeigh, bombed the Alfred P. Murrah Federal Building in Oklahoma City, killing a total of 168 people.

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