A motorist in a rented van drove onto a busy bicycle path near the World Trade Center memorial in Lower Manhattan on Tuesday and fatally struck several people, then emerged screaming and brandishing "imitation firearms" before he was shot by police.

The afternoon incident began with a driver careening on to a pedestrian walkway and bike path, striking several people at a high speed, the New York police said via Twitter. Witnesses described a horrific scene with people diving from the path of the speeding van.

Authorities respond near a damaged school bus Tuesday, Oct. 31, 2017, in New York. A motorist drove onto a busy bicycle path near the World Trade Center memorial and struck several people on Tuesday police and witnesses said.

"There are several fatalities and numerous people injured," police tweeted. "The vehicle continued south, striking another vehicle. The suspect exited the vehicle displaying imitation firearms and was shot by NYPD."

A law enforcement official says at least six people were killed and nine injured. Police said it is too early to tell why the motorist apparently targeted people on the pathway.

An Associated Press photographer on the scene witnessed at least two bodies lying motionless on the path beneath tarps.

Police said the motorist is in custody.

A man who was riding in an Uber along the West Side Highway near Chambers Street said he saw several bleeding people on the ground after a truck struck several people, according to media reports.

A witness said the truck had also collided with a small bus and one other vehicle.

Contributing: Associated Press