About a dozen fires were set in the District late Friday and early yesterday, at least one of them a ferocious blaze in an abandoned building, the D.C. Fire and Emergency Medical Services Department said.

No injuries were reported in any of the fires, most of which apparently began between 1 and 3:30 a.m. yesterday.

"It does appear that there is a pattern" to the fires, said Alan Etter, spokesman for the department. He said officials could not confirm that all of them were set by the same person.

Although no details were available, he said it did not appear that the fires were touched off by a serial arsonist who has plagued the Washington area in recent months.

Most of the fires occurred in the far Southeast or Northeast sections of the city. One fire that authorities also consider suspicious broke out in a parking garage in a building in the heart of downtown Washington, Etter said.

He said that fire damaged a car on the garage level of an office building in the 1100 block of Connecticut Avenue NW.

"That also may have been deliberately set," Etter said.

The most stubborn of the blazes appeared to be the two-alarm fire that began about 3:30 a.m. in a building that was part of an abandoned housing complex in the 100 block of 57th Place SE, Etter said.

That fire, in a building that was part of the East Capitol dwellings, was one of the last in the series and was described by Etter as "very heavy." Flames consumed the interior of the building, and part of its roof collapsed.

Another of the fires that was touched off indoors was in a stairwell of a building in the 600 block of Raleigh Place SE.

Blazes were also reported in piles of trash or trash receptacles in the vicinity of the 5600 block of Call Place SE.

"It was a very busy night for firefighters," Etter said.

The fires are under investigation, he said.