New York: Five people, including a police officer, have died after a shooting at a New York skyscraper.
The lone gunman died from a self-inflicted gunshot wound to the chest after killing the officer and three civilians, officials said.
The suspect was identified as a 27-year-old man from Las Vegas called Shane Devon Tamura, New York police commissioner Jessica Tisch said at a news briefing.
She added that Tamura had a "documented mental health history" but his motive is unknown.
The police officer who was killed has been named as Didarul Islam.
Ms Tisch said at the briefing that he was married with two young boys and his wife is pregnant with their third child.
The New York Police Department has paid tribute to him on X, writing: "He was protecting New Yorkers from danger when his life was tragically cut short today.
"We join in prayer during this time of incomprehensible pain. We will forever honor his legacy."
The shooting happened at 345 Park Avenue - a skyscraper in Midtown Manhattan which houses both the headquarters of the investment firm Blackstone and the National Football League (NFL).
It also houses offices belonging to KPMG, as well as the consulate general of Ireland and a Bank of America branch.
Ms Tisch said in the news briefing that surveillance footage shows Tamura getting out of a black BMW before walking towards the building while carrying an M4 rifle.
She said the footage showed him enter the building's lobby before turning right and opening fire on the police officer.
"He then shoots a woman who took cover behind a pillar and proceeds through the lobby, spraying it with gunfire.
"He makes his way to the elevator bank where he shoots a security guard who was taking cover behind a security desk," Ms Tisch said.
She added that Tamura then called for an elevator which opened in the lobby.
"A female exits that elevator and he allows her to walk past him unharmed.
"He goes up to the 33rd floor... and begins to walk the floor firing rounds as he travelled. One person was struck and killed on that floor," she continued.
Ms Tisch said Tamura then fatally shot himself in the chest.
She added that medication prescribed to Tamura was later found in the BMW he had been driving.
