SOUTH BRUNSWICK - A serious accident involving a military Humvee injured four people and caused the New Jersey State Police to shut down a portion of the New Jersey Turnpike for over an hour.

The accident happened Thursday afternoon on the southbound portion of the Turnpike near Exit 8A in South Brunswick. Witnesses tell News 12 New Jersey that the soldiers were trapped underneath the Humvee.

Michael Watsey says that he and several other drives rushed to help immediately after the accident.

“It’s a military vehicle. They're the ones who protect us,” Watsey says. “I really didn't do much, I took my jack out of my truck and went over and attempted to try and jack it up. Unfortunately it's a Humvee, it was heavy. I couldn't do it.”

New Jersey State Police say that four people were hurt in the accident. One of the injured had to have a portion of their leg amputated at the scene.

One man and one woman are in critical condition at Robert Wood Johnson Hospital. Another man is in serious condition. The condition of the fourth person was not released.

The four people were from the 533rd Brigade out of Fort Totten, New York, according to state police.

The cause of the accident was not immediately known.