BRIDGEPORT — A fire that broke out Sunday morning in an upstairs bedroom of a house at 704 Colorado Ave. was caused by a careless smoker, fire officials said.

Damage to the two-story, single-family dwelling was about $500 to $1,000, Fire Chief Emanuel Firpi said.

He said the fire smoldered on bedding and spread to the mattress. No one — except the family dog — was home at the time of the fire, discovered at 7:34 a.m. Firefighters safely removed the dog and placed it in a cage outside the house. "We got [the fire] early enough," the chief said, adding that a passer-by saw smoke and called 911.

He said while firefighters were able to contain the fire to the bedroom, the entire second floor suffered smoke damage.

Because no one was home, firefighters had to force entry into the house, Firpi said.

The fire was extinguished by 7:55 a.m., he said.

About 20 firefighters and several engines and a rescue ladder truck responded.

The aunt of the homeowner was sitting on the steps of the home Sunday morning. She said firefighters told them about the cause of the blaze and she pointed to a number of cigarette butts left on the lawn. "That's what caused it," said the aunt, who declined to give her name.

The fire was a short distance from the scene of a fatal fire this past winter that claimed the lives of a mother and her two young children.

Tanechia Blackwood, 27, and her sons Eliza Boyd, 5, and Dwayne Dennis Jr., 4 months, died of asphyxia from smoke inhalation in their bedroom after fire ripped through the first floor of their 601 Colorado Ave. home. An accelerant was used to start the Feb. 25 fire in a central hallway on the first floor of the three-story house, officials said. The deaths were ruled homicides.

Despite rewards for information that could help solve the crime, there has been no break in the case, Firpi said.

Also Sunday, a Toyota Rav 4 erupted in flames on Blackman Place. Engine 3 of the Wood Avenue firehouse was released from the house fire to respond to the vehicle blaze. No injuries were reported.