CHICAGO (CBS) — The Chicago Police Bomb and Arson Section will be investigating a couple of suspicious overnight South Side fires.

As WBBM Newsradio’s Bernie Tafoya reports, the fires broke out at 65th Street and Ingleside Avenue in the Woodlawn neighborhood, and at 9124 S. Woodlawn Ave. in the Burnside community.

LISTEN: WBBM Newsradio’s Bernie Tafoya reports

The Fire Department says the residents had moved out of the home at 91st and Woodlawn on Monday, and it erupted in flames at 1:30 a.m. Tuesday.

The fire spread to four other buildings, but did not cause severe damage to those structures.

Fire Department Chief Joe Roccasalva says there was no natural gas explosion, although there are reports from police that an illegal gas hookup was to blame for the blaze.

Meanwhile, police say Bomb and Arson investigators will be looking into the overnight apartment building fire at 65th and Ingleside. The fire was on the first floor of the three-story building.

Police say a 41-year-old firefighter suffered a hand injury, and was treated at University of Chicago Medicine.