A fire that left the occupants of an apartment house homeless late Thursday was accidental, but the cause has not been definitely determined, Fire Prevention Chief Nicholas S. Vilardo said Friday.
Vilardo said the 9:30 p.m. fire started on a mattress in a first-floor rear bedroom and spread to the second floor.
The blaze at 233 15th St. left an estimated $90,000 damage to the 2 1/2 -story, five-unit brick building, owned by Rollin Mills.
One resident, Rena Hamilton, 40, broke her ankle in jumping out a second-story window. Another resident, Samuel Price, 36, was treated for smoke inhalation in Niagara Falls Memorial Medical Center. In all, four persons were aided by the Red Cross, the Fire Department reported.