A gas leak ignited a two-alarm fire at an apartment in San Francisco's Excelsior District early Monday morning and sent two people to the hospital, according to a fire dispatcher.

Fire crews were called to a report of a two-story residential structure fire in the 100 block of Athens Street around 12:50 a.m., the dispatcher said.

When they arrived, they found a busted gas line on the sidewalk and flames shooting up ten to 15 feet high.

Fire personnel upgraded the blaze to a two-alarm fire a short time later, and had the fire under control by 2:13 a.m., according to the dispatcher.

By the time the fire was under control, two people suffered smoke inhalation and were sent to a nearby hospital.

PG&E crews later capped the leak and were repairing the damaged gas line later that morning.

One person was displaced by the fire, which was under investigation later that morning.

An arson investigator was called to the scene, but so far, there's no word on what sparked the fire.