ST. LOUIS (KMOX) - No cause has been determined yet for Sunday’s morning’s apartment fire in south St. Louis.

The fire broke out around 7:30amg in a four-family flat in the 3300 block of Keokuk.  It caused extensive damage to one unit.

One person in that unit was taken to the hospital as a precaution.

Two other units were occupied.

Fire Captain Dan Sutter told KMOX those residents would be allowed to return home by the end of the day.