A gunman killed four people at a Manhattan skyscraper that houses the headquarters of the NFL and the offices of several major financial firms before turning the gun on himself, New York officials have said.

An NYPD officer identified as Didarul Islam, an immigrant from Bangladesh and a father of two whose wife is pregnant, was among those killed. He was working off-hours as a security guard at the time, New York mayor Eric Adams told reporters, describing him as a “true blue hero”.

Authorities offered few details about the three other victims killed by the suspect – two men and a woman. A third male was gravely wounded by the gunfire and was “fighting for his life” in a nearby hospital, the mayor said.

Jessica Tisch, the New York City police commissioner, confirmed that “the lone shooter has been neutralized”. New York police also said the shooter acted alone and was dead.