ARCADIA, FLA., SEPT. 22 -- The fire that destroyed the home of three boys exposed to the AIDS virus was set from inside, and investigators have a suspect but not enough evidence to make an arrest, De Soto County Sheriff Joe Varnadore said today.

Varnadore said the family of Louise and Clifford Ray has been cleared in the blaze, which occurred Aug. 28, four days after the boys were admitted to a DeSoto County elementary school under a court order amid community protests.

The Rays, their hemophiliac sons, Ricky, 10, Robert, 9, and Randy, 8, and their daughter, Candy, 6, were not home at the time of the fire. But the fire and controversy over the boys' attending school forced them to move to adjacent Sarasota County, which has a policy allowing enrollment of children exposed to AIDS.

Sarasota school officials said the youngsters will be admitted to classes Wednesday.

Varnadore would not identify the arson suspect or the type of flammable material used but said he hopes to make an arrest within a few weeks. He and aides said the fire was started in several places within the house. "It was not firebombed," he said.urt order returning the boys to classes Aug. 24, touching off a week of protest.

A family attorney, Judy Kavanaugh, has said the Rays have received more than $50,000 in donations from those sympathetic to their problems.