Four children and a District man died yesterday when an early morning fire raced through a Southeast Washington foster home for children who were wards of the city government.

Nine-year-old Maria Walker, who was also a foster child in the home, was reported in critical condition at D.C. General Hospital, suffering from smoke inhalation, according to hospital records.

Three of the victims were infants, the youngest of whom was identified as month-old Paul Holmes, according to city officials. Police and fire officials would not release the names of the other victims, who included a 55-year-old man who lived at the house; 5-month-old twins, a brother and sister; and a 2-year-old boy recently adopted by Frances P. Walker, who owned the home and was licensed by the D.C. Department of Human Services to care for foster children. Walker apparently was away on a church trip when the fire occurred.

The fire that erupted at 12:47 a.m. at 4286 Southern Ave. SE caused most of the single floor in the brick house to collapse into the basement. Held back by intense heat, it took an estimated 80 firefighters an hour to bring the blaze under control. When firefighters turned a hose on the house, "a piano fell right through the floor," said Rayfield Alfred, D.C. Fire Department spokesman.

"These are very young children. They never had a chance," Alfred said.

The fire was the city's second worst this year. On Jan. 26 nine persons, including seven itinerant Salvadoran laborers, died after a fire swept through a Mount Pleasant row house.

The city requires the approximately 400 homes used by Human Services to have working smoke detectors, according to Robert Malson, a high-ranking agency official.

Alfred said a preliminary investigation showed "no evidence of smoke detectors being in the house." But Dorothy Kennison, head of the agency's family services administration, said a department inspector had found two working smoke detectors in the house during the last inspection in August, one in a hallway near the kitchen and another in a bedroom.

"We consider her Walker one of our best foster parents," Kennison said. "She takes emergency situations at any hour of the day or night," she added.

Diane Bell, who works for Kennison in the foster care division, said, "We are just as devastated as everyone else."

The cause of the fire is still under investigation, but Alfred said it appears to have started "in the basement furnace area" and may have been caused when combustible materials such as "paper and paint" were ignited. A firefighter was injured when a piece of tar from the burning house hit him in the face, Alfred said.

Yesterday afternoon firefighters were still hauling charred debris from the house in the Fort Dupont Park community, a quiet, suburban-looking neighborhood of brick ramblers and split-level homes. Shocked neighbors watched as firefighters set cribs, baby strollers, and living room furniture in the front yard.

According to neighbors, Walker, who is widowed and has lived in the area about 20 years, was away on a church trip. Fire officials said the man who died in the blaze apparently was caring for the children in her absence. The man's body was discovered in the kitchen, and the bodies of the children in a bedroom, a fire spokesman said.

Walker, who returned to the house yesterday morning, was taken to a local hospital, treated for shock and released, neighbors said.

"I think she would have adopted all of them if she could have," said Tawanna Marshall, a neighbor and fellow member of Dupont Park Seventh-day Adventist Church, where Walker was head of the deaconess board and where she was seen with the children nearly every Sunday.

"She loved those children," said Marshall. "I mean she loved them just like they were her own." The 2-year-old adopted by Walker had been a foster child, neighbors said.

The city tries to place no more than four foster children per home, said Bell of Human Services. Kennison said the home was licensed for five children. Bell said the four children living with Walker were placed there through child protective services, which means the natural parents were unable to care for them.

The foster home licensing process, which Bell said can take up to five months, includes eight weeks of training, a home visit and checks for smoke detectors and nonlead paint. Foster care parents receive $287 per month per child for children who are not handicapped. The District government has 2,200 children in foster homes, some of which are outside the city, according to Kennison.

Some neighbors said they smelled gas coming from the fire, and at least one said he heard an explosion. But Katie Magill, a spokeswoman for the Washington Gas Light Co., was quoted in wire reports as saying a furnace and a water heater in the basement appeared to be involved in the fire "only in a secondary way . . . . There was definitely no indication of an explosion."

By late afternoon neighbors were helping Timothy Walker, one of Frances Walker's sons, carry salvageable household goods from the rubble to a car.