SAN FRANCISCO (CBS SF) — Five people were injured early Wednesday when a two-alarm fire damaged two homes in a San Francisco neighborhood, authorities said.

According to San Francisco Fire Department Lt. Jonathan Baxter the blaze in the 70 block of Liebig Street was reported at 12:18 a.m. The fire was first reported around 12:18 a.m. at 70 Liebig St. and then spread to the home next door at 72 Liebig St. Both were detached, 2-story, single-family homes.

Firefighters arrived on scene and found fire extending from the building and people requesting rescues from the second-floor and other locations of the homes.

They forced their way into 70 Liebig St. and found an injured resident near the front door. Firefighters also discovered that the home was piled high with belongings.

“There were a lot contents in the building,” said San Francisco Deputy Fire Chief Mark Gonzales. “It was very hard to get around.”

Five people were transported to hospitals including one child who suffered minor injuries. Two adults are currently in critical condition and two others suffered serious-to-moderate injuries.

“One occupant they found behind the front door,” Gonzales said. “The engine operator did a great job and threw a ladder to the second floor and got the second person out.”

A San Francisco firefighter also suffered an injury to their face and was treated at the scene.

The fire was placed under control around 1:45 a.m. A total of 23 fire apparatuses and 72 firefighters battled the blaze. The American Red Cross was on the scene to assist 17 people who were displaced.

The cause of the fire was under investigation.