St. Louis County, MO (KTRS)  The cause of an overnight fire at a west county apartment complex that sent three people to the hospital is being investigated.

Firefighters were called around 11:45 p.m. Thursday to a fire at Oak Forest Apartments, just off of Lindbergh. The fire quickly went to 2-alarms.

Fourteen people had to be evacuated. Those who were sent to the hospital suffered from smoke inhalation.