Fourteen people were injured when two double-decker buses collided in Times Square Tuesday afternoon, causing a traffic light pole to topple over and smash onto the ground, authorities say.

The buses crashed at Seventh Avenue and West 47th Street, near the famous red staircase of the TKTS booth in the middle of one of the most heavily trafficked areas of New York City. It's not clear what caused the collision, and the NYPD said officers were still on the scene investigating.

Thirteen pedestrians were injured, mainly by the falling light pole and from flying debris from the pole and the bus, FDNY officials said in a news conference Tuesday afternoon.

A tour guide aboard one of the buses was also injured when she was thrown forward and her head became lodged in the dashboard, officials said. She's expected to be OK.

Neither bus driver was hurt.

A witness said he was walking on the sidewalk near one of the buses when he heard what he first thought was some sort of explosion.

"It was only sound, and a lamppost fell down," said Sanjay Shah of Wayne, New Jersey. "Nobody can imagine a bus going on the sidewalk and hitting the lamppost."

Officials said emergency responders initially had difficulty getting to the scene because of heavy traffic in the area, and some firefighters rushed to the scene on foot.

All of the injured victims were treated on the scene. Some were later taken to area hospitals in stable condition and were expected to be released later Tuesday.

"We are very, very fortunate there weren't many more injuries," said an FDNY official.

The NYPD blocked off the area as they investigated the crash, and the closure caused gridlock and heavy delays through the evening rush.