The mystery of Wiltberger Street is who is starting the fires, more than 30 of them in the last year, fires that have melted the buttons on Carolyn Coles' Sunday coat, left Darlene Hart's baby, Steve, gasping for breath at the living room window, shattered friendships and left a once tightly clustered group of neighbors bewildered and suspicious.

Carolyn Coles and Darlene Hart are among some 20 tenants living in a dingy, 10-unit apartment building at 1830 Wiltberger St. NW, a tiny cheerless alley behind the historic Howard Theatre in inner city Shaw.

They live in fear -- fear of the next fire, fear born of not knowing who is doing it.

"I just don't know what to do," says Thomas "Cat Man" Wills, a retired vaudeville dancer, leaning against a white peeling wall outside the building. "I've given up on these fires. I stayawake at night. I watch from outside," but it does no good. The arsonist always returns, unseen.

The fires -- most of them small blazes that have been quickly contained -- have now also generated suspicion and antagonism among the residents, and long-term friendships have deteriorated.

"You know what they're saying about me? They're saying I started those fires," said Coles, a widow who has lived in the building for nine years. "I feel so bad and sad. Those people are my friends and now they don't trust me."

Coles sat dejectedly in her living room, a room that in the past was often filled with friends. Now she sat alone, chain smoking cigarettes and petting her three dogs.

Metropolitan Police Det. Steve Franek, an arson investigator, says the weakening of old friendships is almost inevitable in such situations.

"After a certain number of fires, people stop talking among themselves. They break away from each other and they start talking to the police," said the 14-year police veteran. "They keep it to themselves to a certain point, but then they turn to us. After an arrest, they re-form as a group."

On the subject of who is the arsonist of Wiltberger Street, Franek is tight-lipped. "I can only say that it is under investigation."

"I wish it would stop," said Coles recently as she surveyed her soot-stained walls. Four weeks earlier, she found fire engines outside her building as she returned from the hairdresser. Rushing inside, she found it was her apartment that was on fire.

In fact, there were four separate blazes: in the bathtub, on the bedroom dresser, on top of the stereo and on her best coat. In each case, the fires appeared to have been started with clothing. Coles and other tenants say they do not know how the arsonist gained entrance.

"Look at this coat," Coles said, her eyes wet with tears. She held up the burned sleeve and pointed to a melted button. "This is my Sunday coat. I'll have to throw it away."

There have been many other fires, like the ones set recently in the already fire-scarred first floor hallway and at the doors of various apartments, and like the one set on Hart's kitchen windowsill recently which left baby Steve gasping for breath as smoke slowly filled the apartment.

On Jan. 24, four more fires were set on the first floor, three near Coles' already partially burned door.

"I went to get my slippers and I go by the front door and I see orange flames under the door. I yelled, 'Lord, somebody please help me,'" said Coles. "Then I grabbed a bucket of water and I threw that water on the fire. I think my head is going to pop from all this."

Down the hall, 72-year-old Beatrice ("Miss Bea") Campbell hobbles to the door to show a reporter "her" Saturday fire. Her front door and screen door are heavily charred.

"I was talking on the phone to my son," she said as she leaned on her cane, "and I see the red fire at the door. I started to holler out the window. I don't know what I said now but I sure did holler loud. The firemen came and put it out. I was scared to death, and I still am."

Tenants generally agree there have been at least 30 fires in the last year. Fire Department records show a total of eight reports in that period, but officials note that a single report may reflect several fires that occurred on the same day. Tenants also also said they do not always call the fire department and douse small blazes themselves.

To the residents, the arsonist is a ghost who is able to walk through locked doors, move silently down the dimly lit hallways and leave undetected.

To Franek, it is a real person working alone who will eventually give himself or herself away by the way the fires are set.

"There are three kinds of fires," he said. "There's a lady fire, the man fire and the children's fire. The lady fire occurs in the home, usually the bedroom. They will set a pile of clothes belonging to a boyfriend or husband on fire. Or it wil be a dainty fire. A neat little fire in a garbage bag.

"Then there is the man fire. It's a masculine fire, a macho fire, one with violence to it. It will be at a door or a hallway, and it is usually started with a flammable liquid.

"And then there is the children's fire. It is usually in the home, in the closet or under the bed, some place that's hidden."

Franek is unwilling to apply any of these theories yet to the Wiltberger building. Louie Afable, property manager for the building, also won't say who he thinks is responsible for the fires. "Those arsons are a reflection of the neighborhood," he said, referring to the heavy illicit drug trade on the 600 block of T Street, about 100 feet from the front door of the apartment building.

"We've secured the building. We've changed the locks. We don't have the faintest idea in hell who is doing it," said Afable.

No one seems to sleep much at night, with many tenants catching catnaps during the day.

Hart and her husband, Steve, say they take turns staying awake at night to guard their three children who have been drilled on how to leave the building if a fire starts.

"You're locked in your house and they start a fire," say Coles wearily, "and you don't know if you can get out. So you can't sleep because you've got to be awake to see the blaze so you can put it out."

"You never get sleep around here," says Hart. "So when I'm afraid to sleep, I pray sometimes. I ask the Lord, 'If there's another fire, please let everyone in the building get out okay.'"