A Brigham Young University police officer participating in an emergency driving course was injured when his car rolled Monday.

Sgt. David Adams was attempting to execute a "J-turn," in which a police officer puts the vehicle in reverse and turns the wheel sharply to swing the front end around. Although he was going less than 15 mph, the Chevy S-10 Blazer rolled."It was so top-heavy that it just rolled over onto its top," said Lt. Greg Barber of University Police.

As the Blazer rolled, Adams stuck his arm out the open driver-side window to brace himself, Barber said. He sustained a broken ulna just above the wrist, two broken fingers and lacerations on his hand and arm.

Adams, who has been with University Police for about five years, was participating along with other officers in an "emergency vehicle operations driving" training exercise.