Hanger and planes damaged in fire at Spirit of St. Louis Airport

CHESTERFIELD, MO (KPLR) - Fire investigators are still trying to determine what started a massive blaze at Spirit of St. Louis Airport in Chesterfield that damaged several planes.

The fire started 1 am this morning inside building divided into a dozen hangars.

A passerby reportedly spotted the fire and called 911.

Video from Bommarito Automotive SkyFox shows the aftermath.

Several departments responded to the three-alarm fire, but by the time firefighters arrived part of the building was engulfed in flames.

Seven planes were inside the area of the hangar that caught fire, all of them were damaged.

Authorities say two of the planes sustained fire damage, 5 had damage from smoke and debris.

There was a car inside the hangar that was also damaged.

At this time investigators believe the fire started inside one of the units where a plane was being stored.  That are separated by a wall, but they don't go all away up to the ceiling.

There were some flammable materials in the hanger, like aerosols, fuel cans and propane tanks.

But it has yet to be determined if that's what started it.

At one point the building had to be evacuated when the fire reignited.