A predawn fire, believed to have been caused by an electrical failure, sent smoke pouring into upper floors of a senior citizens' apartment building in Waukegan, Ill., yesterday, killing eight tenants, injuring six and leaving 21 homeless, authorities said.

Other Christmas Day fires killed 10 persons -- two in a Baldwin, Mich., foster home; two near St. Albans, W.Va., in a blaze apparently sparked by electrical failure in Christmas lights; two in California homes where Christmas trees caught fire; two in a Tennessee house fire apparently caused by a cigarette, and a mother and daughter in a suburban Minneapolis house fire.

The fire at the nine-story Karcher Retirement Hotel started about 2:30 a.m. in a first-floor clothing shop, swept into the lobby and sent dense smoke up the elevator shaft, Lake County Coroner Barbara Richardson said. The dead were found on upper floors, apparently victims of smoke inhalation.

The death toll might have been higher had 18 residents of the 52-unit building not spent the night with relatives for the holidays, she said.

In the house fire about six miles from St. Albans, a 9-year-old child awoke to notice the Christmas tree ablaze and escaped with her sister and father, fire officials said. The couple who owned the home died.

The owner of the Baldwin foster home removed two residents but could not reach two others who died in a fire at 4 a.m., a Lake County, Mich., deputy said.

Authorities in La Puente and Bell, Calif., said trees caught fire in two homes, killing a teen-ager by smoke inhalation and a woman who suffered heart failure.

In Covington, Tenn., officials said smoking in bed might have caused the fire that killed a 78-year-old woman and her son.