Louisiana State Police say a trooper was shot in the head and critically injured when he tried to stop a driver suspected of being drunk or drugged in southwest Louisiana.

A message from the head of state police on the department's Facebook page says other drivers stopped the alleged gunman and helped the officer until paramedics arrived Sunday.

Capt. Doug Cain confirms that the officer was shot in the head.

Col. Mike Edmonson, head of state police, said the trooper's name and status will be released as the investigation continues. He asked for prayers and well wishes for the officer and his family.

The Facebook message's subject line read "Trooper Critically Injured — Prayers Needed."

Other details were not immediately available.