WASHINGTON — The nation’s top law enforcement leaders joined officers and family members in Northwest D.C. on Friday to mark a somber anniversary.

Twenty years ago, a gunman opened fire inside D.C. police headquarters, killing two FBI special agents and a D.C. police sergeant.

“I assure you everybody in the audience remembers exactly where they were on November 22nd, 1994,” said D.C. Police Chief Cathy Lanier during memorial services at St. Patrick’s Church. “We first got the news that the shooting was at police headquarters. We thought ‘surely that’s a mistake.’ Sadly, we quickly learned that it was not a mistake.”

Gunman Bennie Lee Lawson had been able to walk into a squad room on the third floor of police headquarters and open fire. Investigators believe he was targeting homicide investigators, including the unit’s commander, after being questioned in connection with a triple murder the week before.

Killed were FBI Special Agents Martha Dixon Martinez and Michael Miller, and Metropolitan Police Sergeant Henry “Hank” Daly.

“We hail their valor and we salute their singular courage,” said Attorney General Eric Holder. “This city is different 20 years later because of the great work that they did.”

Added FBI director James Comey: “We remember their bravery, and because we remember them, even 20 years later, they have never left us.”

The attacker was wounded in a shootout and died after turning a gun on himself.

Another FBI special agent was shot and seriously wounded, and a 15-year-old boy was shot in the leg.

The injured agent, John Kuchta, survived and continues to serve with the FBI.

The services at St. Patrick’s were followed by a wreath-laying ceremony at the National Law Enforcement Officers Memorial.

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