Investigators on Thursday ruled that a fire at a Miami Beach apartment complex started accidentally.

The fire at Mantell Plaza began about 6:30 p.m. Wednesday in a third-floor unit, Miami Beach Fire Rescue said. The fire was contained to the unit, but other parts of the five-story building suffered smoke and water damage.

No injuries were reported. The fire displaced about 100 people, who received assistance from the Red Cross.

Inspectors were checking the building to see if it was structurally sound.