A smoky three-alarm fire broke out last night in the old Lansburgh's department store building, which now houses two dozen arts and cultural groups and a number of D.C. government offices.

No injuries were reported in the blaze, which fire officials said started in electrical wiring in city agency offices on the fourth floor.

They said the fire was apparently concentrated inside wall partitions on that floor, but that flame and smoke also spread to the two upper floors of the six-story building in the 400 block of Seventh Street NW.

An estimate of damage was not immediately available.

Fire officials said the blaze was reported about 10 p.m. and was largely extinguished within about 45 minutes. They said three alarms were issued as a precaution because of the building's age, the difficulty of locating the blaze and the possibility of its spreading.

The blaze brought about 100 firefighters and 45 pieces of equipment to Lansburgh's, which opened at Seventh and E before the Civil War.

After the store closed in 1973, the federal government became the building's owner through the Pennsylvania Avenue Development Corporation, which leased space to the D.C. government.

The arts groups lease their quarters from the city, according to a PADC official.

Several persons were in the building when the fire broke out. One said the Nubian Theater Company was rehearsing on an upper floor when a knock on the door was answered to reveal a hallway full of smoke.