Two horses suffered minor injuries when the trailer they were traveling in overturned Friday afternoon on a busy highway in northern New Jersey, causing major traffic delays at the start of the holiday weekend.

The accident occurred when a small horse trailer being pulled by a truck overturned in the southbound lanes of Route 287, according to State Police Sgt. Stephen Jones. The truck did not overturn during the accident, which may have been caused by driver error, Jones said.

One of the horses got loose, but was restrained shortly afterward, Jones said. The second horse was trapped for some time before it was removed from the trailer. The horses had only minor injuries and were put on another trailer to continue their trip, Jones said.

Three lanes of traffic were closed by the accident, which took about an hour to clear up