Fairfax County police said yesterday they had reopened an investigation into the mysterious death of a 25-year-old clerical worker eight years ago after receiving information from Florida authorities investigating a bizarre kidnaping-rape case there.

Deborah R. Fitzjohn's death in 1978 was termed suspicious by Fairfax County police, but no one was charged in the case, according police spokesman Warren R. Carmichael.

On Nov. 23, authorities in Brevard County, Fla., arrested John Brennan Crutchley, 39 -- the man Fairfax police say was the last person to see Fitzjohn alive -- on charges of rape and aggravated battery. Authorities said he had raped a 19-year-old woman, inserted "an intravenous device" into one of her veins and drunk a large amount of her blood.

Crutchley is also under investigation in the deaths of five other woman in Brevard County, according to a spokeswoman for the Brevard Sheriff's Department.

Fairfax police spokesman Carmichael said: "As a result of information developed in cooperation with Florida authorities, coincidental to the arrest of Crutchley, we have reopened our investigation into the death of Fitzjohn."

Police said they believe that Crutchley, whom they described as a social acquaintance of Fitzjohn, saw her when she visited his house trailer at Waple's Mobile Home Estates near Fairfax City on Jan. 27, 1978, immediately before she disappeared.

Fitzjohn's body was found by a hunter near the Fairfax-Loudoun County border in October 1978, Carmichael said. Because her remains were badly decomposed, no definite cause of death was determined.

Crutchley was interviewed by Fairfax police after Fitzjohn's disapperance, Carmichael said.

Crutchley is being held in lieu of $500,000 bond in the Brevard County Jail in Titusville, Fla.