A man trapped underground after an explosion at Bensalem gas station late Tuesday afternoon is believed to be dead, an official said Wednesday morning.

Bensalem Fire Rescue Battalion Chief Rob Sponheimer told reporters at the scene at dawn that rescue efforts had halted in the face of high levels of gas fumes where the man was trapped. Operations had shifted to recovery mode, he said, meaning authorities believe the trapped man has died.

He said crews would attempt to resume recovery operations later Wednesday morning.

"Crews have been working all night on this incident. We are in the process of breaking down a lot of the equipment," Sponheimer said

Bristol Pike also reopened after having been closed all night while rescue operations were under way.

Another man was injured in the blast and taken to a hospital in critical condition with extensive burns.

No names have been released.

Firefighters were called to the Liberty Gas Station at 1214 Bristol Pike about 5 p.m. Tuesday to perform a technical rescue.

A live videostream from the 6ABC helicopter showed firefighters working over an opening in the ground surrounded by fractured concrete.

Later, crews were directed away from the scene because of fumes and relocated to the Woodhaven Mall parking lot.

As of 11 p.m., emergency responders were continuing to try to remove the man from underneath the debris.

Firefighters and equipment were called in from Philadelphia and neighboring Bucks County communities to assist with the rescue operation.

The cause of the explosion is under investigation.