By COLLEEN LONG
Associated Press Writer
NEW YORK

A single mother who died in a mysterious fire with her four children committed suicide and her teenage son's death was a homicide, the medical examiner ruled Thursday, clearing up questions about whether the boy had been responsible for the deaths.

Leisa Jones died from smoke inhalation in the mysterious blaze at her Staten Island home last week in a case briefly believed to be an accidental fire before it became a homicide investigation.

Firefighters responding early July 22 found the charred bodies of Jones and two daughters, ages 7 and 10, in a front room, and that of her 14-year-old son, C.J., slumped over a bed in a back bedroom. A 2-year-old son pulled out alive died at a hospital of smoke inhalation.

Police said later that day that the throats of the two girls and C.J. had been slashed. They also said a razor had been found under C.J.'s body and that he had a history of playing with fire. It was theorized that he might have killed his family, set the blaze and cut his own throat.

But an initial round of autopsies found that Jones and C.J. both had ingested some type of drug, according to two law enforcement officials.

Also, a badly damaged note with the words "am sorry" that was found in an another room was written by Jones. It remained unclear whether it was a suicide note, but that discovery _ combined with the initial drug evidence _ led to suspicions she killed her children.

The pills did not cause their deaths. C.J. died from his neck wound and his death was ruled a homicide, said Ellen Borakove, spokeswoman for the city medical examiner's office.

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Associated Press writer Tom Hays contributed to this report.

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