A massive fire tore through a Ravenswood apartment building and spread to a house next door early Saturday on the North Side.

A second alarm was called for the fire about 1 a.m., bringing more than 100 firefighters to the blaze at a three-story building in the 5100 block of North Paulina, according to the Chicago Fire Department.

Flames spread to a two-story house on Winona Street, fire officials said. No injuries were reported.

The fire was under control by about 1:30 a.m., officials said. It wasn’t clear how many residents would be displaced.