Police push to ID gunman involved in shooting of UnitedHealthcare boss

Members of the New York police crime scene unit pick up cups marking the spots where bullets lie as they investigate the scene outside the Hilton Hotel in midtown Manhattan where Brian Thompson, the CEO of UnitedHealthcare, was fatally shot. Picture: Stefan Jeremiah/AP

The gunman who killed the chief executive of the largest US health insurer likely left New York City on a bus soon after the brazen ambush that has shaken corporate America, police officials said.

But he left something behind: a backpack that was discovered in Central Park.