PHOENIX – More than 50 people were evacuated from a Phoenix apartment building early Wednesday after a fire broke out in a third-story unit, first responders said.

When Phoenix Fire Department crews arrived at the complex near 19th and Dunlap avenues around 2:45 a.m., the blaze was working its way through a third-floor apartment.

There were no reports of injuries.

First responders said renters from the first and second floors were cleared out of their homes because of the fire’s potential to spread.

A fire department spokesman said three families were displaced.

Cause of the blaze is under investigation.