NEW YORK (CBSNewYork/AP) — More than 200 people gathered Thursday to honor a security guard who was gunned down at a federal office building in the Hudson Square area by a former government employee who later killed himself.

The Federal Protective Service held a memorial Thursday night in Manhattan to remember Idrissa Camara, 53.

The officer was working for FJC Security Services at a federal office building at 201 Varick St. this past Friday.

“The world lost an incredible human being when Idrissa Camara tragically died in the line of duty,” Joshua Primrose, a vice president with FJC Security Services said at the service. “His courageous actions saved others and we will never forget.”

Police have said the gunman, Kevin Downing, 68, entered the building around 5 p.m. that day with guns hidden in a bag.

Downing pulled out a gun and shot Camara in the head as he approached the metal detector at the security screening area, authorities said. They said Downing then walked through the metal detectors toward the elevator and shot himself in the head.

PHOTOS: Fatal Shooting At Varick Street Federal Building

Camara was rushed to Lenox Hill HealthPlex, where he was pronounced dead at 5:55 p.m., police said.

Detectives said Downing, a former economist, was fired from the Federal Bureau of Labor Statistics several years ago. The BLS has an office on the eighth floor of the building on Varick Street.

Lawsuits and other documents show Downing thought he was fired as retaliation for blowing the whistle on alleged corruption and public waste, CBS2’s Ilana Gold reported.

Camara’s shift had ended at 4 p.m. but he had agreed to stay longer.

“His co-workers and his community, which he loved and respected, will remember him as the sort of man who would give them the shirt off his back if he was asked,” Primrose said.

Carolyn Harley, who worked at the Varick Street building with Camara for three years, said the mood remains somber among fellow security guards.

“The guards are very, very hurt,” she said as mourners wept beside her. “We’re all hurting, but nevertheless we made an oath to do our job and even in mourning we’re going to do it to the best of our ability.”

On Thursday night, Camara was posthumously awarded the director’s citation from the Federal Protective Service.

Camara is survived by a wife and three young children.

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