Firefighters battling a large blaze at a three-story building on Center Avenue in Butler briefly feared for the safety of one of their colleagues Sunday morning when they heard the call on the radio — “Mayday.”

Unaccounted for, fire officials said, was Kevin Smith, a member of an attack crew that went into the building that houses eights apartments and a restaurant.

Smith, assistant fire chief for the South Butler Volunteer Fire Department, was leading his crew, manning the nozzle of the fire hose, when he got separated from the others.

“He got caught inside by conditions deteriorating,” said Butler Fire Department Capt. Kevin McAfee.

About that same time, a Butler engine sounded its evacuation alarm. The roof was giving way, smoke was building up and flames were growing.

“He was looking for a way out,” McAfee said of Smith, who moved toward a window on the third floor.

The other firefighters inside noticed Smith missing and radioed a distress call.

“The crew inside was calling ‘Mayday,’” McAfee said.

Crews outside saw the endangered firefighter hanging out the third-floor window on the side of the building. Officials said Smith’s body — from the hips up — was out of the window.

He was waving his arms. Fortunately, he was wearing an air mask and breathing pack.

“So breathing wise, he was fine,” McAfee said. “But it was scary. It was a scary few minutes. It’s a long drop from three stories.”

Firefighters on the ground immediately hatched a rescue plan. They got extension ladders and quickly deployed them between the roof of an adjoining house and against the building on fire — to the distressed firefighter.

The ladders would serve as a makeshift bridge for Smith to crawl across.

But, it turned out, he took a more conventional path out of harm’s way. He used another ladder, which rescuers positioned under the window from which he was hanging, to climb down to safety.

“That was a pretty amazing feat,” McAfee noted, “because that ladder was straight up and down.”

A Butler Ambulance Service crew examined Smith but he apparently was uninjured.

An ambulance medic refused comment, saying only that “no one needed medical care” in the wake of the fire.

“Everything’s fine and Kevin is fine,” said Steve Martin, a South Butler firefighter, who declined further comment.

Smith even stayed on duty, officials said, remaining there for the rest of the fire fight.