A fire injured 16 people at an apartment building for the elderly and disabled early Thursday, forcing firefighters to use a ladder truck to rescue some residents from upper floors, officials said.

The fire in the Eastgate complex was reported shortly before 4 a.m. in a first-floor apartment and sent smoke throughout the four-story building. Eight apartments were seriously damaged.

"The smoke was heavy in the halls. It was hard to breathe," resident Harriet Brown told WTNH-TV.

Two female residents were in critical condition at Bridgeport Hospital, and a man was in fair condition, hospital spokesman John Cappiello said. The man and one of the women were in the hospital's burn treatment center, and the other woman was in intensive care, he said.

The other victims, including a firefighter with a shoulder injury, were brought to Waterbury and St. Mary's hospitals.

Injuries to the six people taken to Waterbury Hospital were not considered serious, a hospital spokeswoman said. A message was left with St. Mary's Hospital.

Waterbury Mayor Mike Jarjura, who arrived at the fire while crews were still rescuing residents, said people who were already out of the building were helping others, wheeling them out in wheelchairs and calling their families on cell phones to offer reassurances and updates.

"I would say it was organized chaos," Jarjura said.

Firefighters contained the blaze in about 20 minutes, said Ray Lodge, director of communications for the Waterbury Fire Department. The cause remained under investigation.

Rescuers went door-to-door to get people out and used a ladder truck to help several others to safety. The dozens of residents who weren't injured were brought to the other building in the complex.

Most of the injuries were smoke inhalation, fire officials said. None of the victims' names were released.

The apartment complex was built in 1973. It includes subsidized rental apartments for low-income senior citizens and people with disabilities. The Red Cross was helping find shelter for those whose apartments were severely damaged.