NEWARK, N.J. (AP) - Two commuter buses collided in New Jersey's largest city Friday morning, pushing one of the vehicles onto its side, killing one of the drivers and critically injuring seven other people, authorities said.

The person killed in the Newark crash was the driver of a New Jersey Transit bus that had no passengers when it slammed into the side of another NJ Transit bus that was carrying about 20 passengers around 6 a.m.

Mayor Ras Baraka said 19 people were injured, including seven critically.

"We're praying for all of those in the hospital," he said.

Investigators are trying to determine if the driver who died ran a red light, Baraka said.

Video from news helicopters showed the two tangled buses came to rest on a median. The bus that was struck was on its side, its frame bent and the other bus lodged in its undercarriage. Firefighters could be seen pulling passengers through a side window and loading them onto waiting stretchers and into ambulances.

The crash occurred at Raymond Boulevard and Broad Street as the bus without passengers began its route between Newark and Dunellen; the other bus was traveling between Irvington and Clifton, NJ Transit spokeswoman Nancy Snyder said.

The Essex County prosecutor is investigating the crash.

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