A donation of pet oxygen masks last month and quick work by firefighters, veterinarians and bystanders helped save the lives of 21 dogs who were in a burning building early Saturday morning.

One other dog, however, died, officials said, possibly from smoke inhalation.

The fire started in Christal K-9, 3115 W. Sixth St., a business that provides pet services, and smoke from the fire also damaged Jazzercize, which is located next door.

People arriving at Jazzercize at about 6:30 a.m. Saturday smelled smoke and called 911 even though they did not see a fire, officials said.

When the first company of firefighters arrived, they too reported there were no flames, a fire department press release said. As they continued to investigate, they found dense smoke and fire inside Christal K-9.

Firefighters began hauling out dogs in cages as they put out the fire, said Hank Booth, a radio personality who works nearby at KLWN-AM 1320 radio station.

The cages were lined up in a row along the curb of the businesses as smoke poured out of Christal K-9, Booth said. Some of the dogs were lying in their cages, some were lying on the pavement, and others were being held in people’s laps, he said.

Firefighters, veterinarians and bystanders strapped the resuscitation masks on the dogs’ faces and began pumping air into their lungs.

“It looked like a battle zone,” Booth said. “Everybody who was there was trying to do something. So many people were there helping dogs.”

Staff from the Lawrence Humane Society and City of Lawrence Animal Control eventually transported all the dogs to area veterinary clinics for treatment, according to a press release.

Booth, who knows Cedric Devin, the owner of the business, said he was told the fire started when a fan motor froze, overheated and caught fire. Fire officials had not released an official cause by Saturday evening.

About a dozen resuscitation masks for dogs in small, medium and large sizes were donated last month to the Lawrence Fire Department along with a DVD training video, said Darin Cox, a board member with the Chinese Shar-Pei Club of America.

The club held its national specialty show last month in Lawrence. The club began donating the oxygen masks a couple years ago to thank communities for sponsoring their shows, Cox said.

“I’m thrilled to hear this,” Cox said Saturday of the dogs’ rescue with the help of the donated masks. “I’m just really glad we were able to make a difference for these animals.”