(KMOV) -- Firefighters were called to the scene of a 3-alarm blaze at a 7-story building in north St. Louis late Sunday night.
The fire started in the 5000 block of San Francisco near Kingshighway just before 11 p.m.
According to St. Louis Fire Chief Dennis Jenkerson, heavy fire was seen coming from the fifth floor of the interior courtyard area of the building when crews first arrived on the scene.
Crews began fighting the blaze but had to evacuate the building after the fifth floor collapsed nearly a foot underneath them.
They got the blaze under control, though Jenkerson said it was not easy.
Officials say the fire caused heavy damage to the fifth floor of the building. The sixth floor of the building sustained heavy smoke damage, and damage could be seen on the seventh floor.
It is unknown if the building was occupied at the time of the fire.
No injuries were reported.
The cause of the fire is under investigation.