Essex, MD – ESSEX, Md. (AP) — Two firefighters were rescued from beneath 2 1/2 stories of debris after being trapped there for more than an hour following a natural gas explosion, Baltimore County fire officials said.

A duplex was leveled in the explosion late Sunday afternoon, which injured two civilians and pinned the firefighters in the basement. Two other firefighters were injured when they were hit by flying debris, Battalion Chief Michael Robinson said.

The trapped firefighters were flown to Shock Trauma with burns after being rescued, fire officials said.

None of the injuries were expected to be life-threatening, Robinson said.

An advanced tactical rescue team helped to get the firefighters out by removing debris piece by piece, Robinson said.

He said they were lucky to be caught in a pocket of air, which allowed them to communicate with rescuers and help get themselves free.

“The entire house was leveled. It was a miraculous thing,” Robinson said. “They could have been crushed by the debris.”

Firefighters responded to a call about a gas leak at 5:19 p.m. from 557 Chalcot Square in Essex. When firefighters arrived, they sent an emergency distress signal. But within minutes, the home exploded and two of the firefighters were trapped.

About 120 firefighters responded to the scene, Robinson said.

Lt. Tim Robinson at fire dispatch said the trapped firefighters remained in contact with crews by radio.

“They said, ‘Get me outta here,”’ he said.

Fire officials said the leak likely originated from inside the house, with a problem with a water heater or a cooking appliance.

Rob Gould of Constellation Energy Group said it doesn’t appear the BGE system outside the duplex contributed to the explosion. Gould said the utility will check the gas meter from the duplex Monday.