Updated 7:30 a.m.
The fire destroyed Building 20 at Ridge Pointe, Marietta public safety officials say.
The Marietta Fire Department received the call at 11:38 p.m., and the first firefighters on the scene saw flames coming from a second-floor apartment.
The initial investigation found that the fire started in a bedroom in that apartment.
Nine fire units battled the blaze, which ruined all 10 apartments, the Fire Department said. It put the number of people displaced at 45.
More than 40 people lost their homes to a fire overnight at the off Franklin Road in Marietta.
WSB-TV said the blaze started in a bedroom and destroyed one of the buildings in the complex at 720 Franklin Rd.
No one was hurt.
Both and firefighters were putting out hotspots at 4:30 a.m. but began leaving over the next half-hour, WSB-TV reported during a live broadcast from the site.
Flames were shooting through the roof of the three-story building when firetrucks arrived, WSB said.
The cause of the fire is under investigation.