At least 45 people were injured when two New Jersey Transit buses collided inside the Lincoln Tunnel Monday morning, temporarily shutting down the center tube and snarling traffic at the end of rush hour, officials said.

According to NJ Transit, a bus on the 127 line from Ridgefield, New Jersey, was headed to the Port Authority Bus Terminal in Manhattan when it rear-ended a bus on the 128 line that was also headed to the bus terminal. The crash happened around 8:40 a.m.

An FDNY spokesman said that of the 45 injured, 41 people suffered minor injuries, three people were in serious but stable condition, and one person was in serious condition.

A NJ Transit spokesman said the 127 line bus had 37 passengers aboard at the time the crash. He said it was not known how many passengers were on the 128 line bus, but that it was full.

The crash shut down the center tube for several hours, causing heavy delays at the tunnel in both directions. The tube was reopened to traffic around 11 a.m., the Port Authority said on its website.