A New York City police officer and three other people were killed in a shooting in Midtown Manhattan on Monday evening, police confirmed at a late-night news conference.

The New York police officer killed in a mass shooting in a Manhattan skyscraper on Monday was an immigrant who left behind a pregnant wife, two young sons and distraught parents, while friends and officials in Bangladesh and the United States described him as a hero.

Blackstone, one of the world’s largest investment firms, confirmed one of its employees, Wesley LePatner, was among those killed. A Yale graduate, LePatner was a real estate executive, according to Blackstone’s website, and spent more than a decade at Goldman Sachs before joining the firm in 2014.