Emergency crews battle an apartment building fire on Sherbrook Street. (CBC)

Nineteen people needed treatment in hospital following a fire in a Winnipeg apartment building early Saturday morning.

Fire officials said 14 had suffered smoke inhalation and one firefighter hurt his knee.

Four members of one family were also taken to hospital in unstable condition. However, their condition improved and by Saturday evening they had been released.

"I talked to one witness who says the fire, paramedics and police got here at about seven this morning," CBC's Sheila North-Wilson reported Saturday. "And when he came out to look, there were flames shooting up at least 20 feet, he figures. There are trees next to the building singed."

According to North-Wilson, police have several people in custody in connection to their investigation into the fire.

Frank Perrotti lives near the building and told CBC News the fire was intense.

"It was serious. I never saw a fire like that in my life," he said.

A few hours after it started, one of the building's walls collapsed.

An estimated 50 people have lost their homes and all their possessions.

One of the residents of the building who was able to get to safety was Getachew Haregewin, who said he was relieved he was home at the time and able to alert his 12-year-old hearing impaired daughter.

"If I were not home, definitely she would've died," Haregewin said. "Because she can't hear."

He added the girl's hearing aid was left behind in the rush to escape.

Haregewin got out with only his clothing, with no socks and no jacket.

Two buildings next to the one that was on fire were also evacuated.

The fire was at 577 Sherbrook St.

Damage is estimated at $600,000.