MARLOW, Okla. (AP) _ A fire suppression team was preparing Monday to cap a natural gas pocket that caught fire and caused an oil rig blowout, injuring three men, authorities said.

The blowout occurred about 4:45 a.m. Saturday at the Thomas Rig No. 1, 13 miles northeast of Marlow in south-central Oklahoma, fire authorities said.

Carl Bentley, president of Mack Energy Co., which leased the rig from the Thomas Drilling Co., said the company has called in Boots and Coots Fire Suppression of Houston to cap the pocket and extinguish the fire.

''We're proceeding with plans to cut the equipment off, remove the rig and cap the well,'' he said, adding, ''It isn't endangering anything.''

He said the fire occurred when a natural gas pocket was tapped unexpectedly and escaping gas ignited.

Ollie Suttle, a tool pusher for Thomas Drilling Co., suffered second-degree burns on his upper arm and back, Bentley said. Suttle was listed in good condition Monday at Duncan Regional Hospital, a hospital spokesman said.

Roger Seymour, 25, of Marlow, and Gary Davis, 24, of Rush Springs, suffered minor burns. They were treated and released Saturday.