A two-vehicle crash Tuesday morning claimed the lives of a father and two of his children and left a third child with critical injuries.

Oklahoma Highway Patrol reports show the crash occurred about 9:25 a.m. on U.S. Highway 70 at Simpson Road. Todd Leonard, 29, Oklahoma City, was pronounced dead at the scene from massive injuries. His 3-year-old daughter and 1-year-old son also died from massive injuries at the scene. His 7-year-old son was airlifted from the scene 4.7 miles west of Oakland, and flown to OU Medical Center in Oklahoma City, where he was admitted in critical condition from multiple injuries. All four of the victims were pinned in the wreckage of their car for about 30 minutes. They were freed by Madill firefighters.

The preliminary investigation shows Leonard and his children, were eastbound on the highway in a 2012 Mercedes when the car was hit by a westbound 2007 Kenworth when the semi went left of center. The driver of the truck, identified as 25-year-old Stanley Matsinger, Grandbury, Texas, was not injured.

U.S. 70 was closed for 4 hours and 40 minutes as a result of the crash.

Seat belts were in use in both vehicles. Air bags deployed in the Mercedes.

The cause of the crash remained under investigation late Tuesday afternoon.