The Nissan Pathfinder that prompted police to close off parts of New York's Times Square contained bomb-making materials, the city's mayor said.

Mayor Michael Bloomberg said three propane tanks, two gasoline containers, batteries, consumer-grade fireworks and a locked metal box that resembled a gun locker were found in the vehicle.

The wiring around the device "was nothing that looked amateurish," Bloomberg said.

"It certainly could have exploded and caused a pretty big fire and a decent amount of explosive impact," he said.