Follow along for live updates on the New York City shooting, where police investigate motive after five people, including the gunman, were killed in the Monday shooting.

Police lined up four rows deep in front of a mosque on Thursday to pay respects to a fellow officer who was among the victims of a gunman's rampage at a New York City office tower. Fire trucks bore a huge American flag down the street ahead of services for Officer Didarul Islam,

New York City has some of the toughest gun laws in the nation. But Monday’s mass shooting showed their limits, security experts said.