NEW YORK – A New Jersey transit bus rear-ended a private bus carrying Canadian schoolchildren inside the Lincoln Tunnel on Wednesday morning, injuring at least 18 people and slowing traffic on one of the busiest routes for commuters entering and leaving New York City, authorities said.

None of the 26 students and two adults from the Toronto school was hurt, according to Anna Caputo, spokeswoman for the Toronto District School Board. The group was heading to New York for a graduation trip, she said.

The crash happened at around 9:30 a.m. in the center tube on the New York side of the tunnel connecting it with New Jersey, said Joe Pentangelo, spokesman for the Port Authority of New York and New Jersey police, which operates the tunnel.

The extent of the injuries of the approximately 60 riders on the NJ Transit bus that was heading from Cresskill, New Jersey, to the Port Authority Bus Terminal was not known. At least two people were taken out of the tunnel on stretchers and two others walked out with the help of emergency personnel. People with bloody noses were being treated at a triage station set up outside the tunnel.

There are delays of up to one hour heading into New York because traffic is being diverted to the south tube.

The Port Authority says 42 million vehicles a year travel through the tunnel. The tunnel is comprised of three tubes built beneath the Hudson River.