FRIENDSHIP, Okla. (AP) — Authorities in southwestern Oklahoma say a volunteer firefighter has died while battling a house fire.

The Jackson County sheriff's department says 54-year-old Madison "Maddy" Lee Clinton Jr. was killed while battling a house fire in Friendship, about 137 miles (220 kilometers) southwest of Oklahoma City. Clinton was the assistant chief of the Friendship Volunteer Fire Department.

The fire broke out at about 5:30 p.m. Friday and authorities say the structure was engulfed in flames when firefighters arrived. Officials say Clinton was attempting to extinguish the flames when part of the structure collapsed, pinning him underneath.

The cause of the fire has not been determined but officials say the structure was destroyed.