A northbound commuter bus being used to train a half-dozen bus drivers caught fire Friday morning, causing substantial traffic on Route 17, according to the Ramsey Fire Department.

Coach Bus 7115, based out of Mahwah, was traveling up and down Route 17 as new drivers were taking turns learning to drive it when the occupants noticed smoke and flames coming from the bathroom at the rear of the bus, according to Ramsey Assistant Fire Chief Randy Sterbinsky.

The drivers pulled over by the Lake Street exit in front of the Pathmark shopping center in Ramsey at about 11 a.m., and all occupants evacuated the bus safely, Sterbinsky said.

No one was injured in the incident, he said.

“The back third of the bus was fully involved,” Sterbinsky said.

Three engines from Ramsey and a crew from Upper Saddle River fought the fire for about an hour and a half Friday, he said.

The bus was being towed away and lanes on Route 17 North were being reopened to traffic by about 12:30 p.m., officials said.

The cause of the fire is unknown at this time.