Firefighters believe the blaze started on a back balcony of the Rockport Apartments on Naim near S. Gessner in southwest Houston.
The back units were unoccupied and did not have electricity. Firefighters called for a second alarm as a precaution, but were able to put out the flames. The building received heavy damage to the exterior, but the interior has only minimal damage.
"There is no electricity. There is no apparent cause anywhere near the area that is burned," said Fire Chief John Searman with the Houston Fire Department. "There is no electricity, nothing we can put it off on -- so it almost has to be arson.
Firefighters also conducted a door to door search and were able to get all the residents out. No one was hurt.
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