CHARLOTTE, N.C. — Charlotte city officials confirmed that two people died in the five-alarm fire that ignited Thursday morning in the South Park area of Charlotte.

Mayor Vi Lyles and Charlotte first responders announced the deaths Friday afternoon.

Demonte Sherrill, a father and family man, was identified as one of the two who died in the massive fire. The name of the second victim was not released.

"We haven't a had a fire like this in decades. Maybe ever," said Charlotte Fire Department Chief Reginald Johnson.

Fifteen people, including a crane operator, were rescued by firefighters Thursday. The two people who died in the 2,000-degree fire were believed to be on the sixth floor of a building before flames tore through the area, officials said.

"The fire spread rapidly," Johnson said at the news conference Friday.

The fire broke out about 9 a.m. at a construction site off Liberty Row Drive near Fairview Road, near SouthPark Mall. A video tweeted by Charlotte firefighters just before 10 a.m. shows large flames and heavy smoke.

Investigators think the fire started in a trailer used to spray insulation into the building's walls, Johnson said.

The chief said investigators aren't sure what set off the blaze and haven't been able to do a thorough investigation of the trailer.

“Obviously, the building's still in a state where it is not safe for all of our members to go in,” Johnson said.

Firefighters themselves had to be rescued after they became trapped while rescuing others in the fast-moving fire. One of the firefighters heard the cries of people trapped on the sixth floor but couldn't see them through the smoke, Johnson said.

“They were going by sound, trying to get to them but were unable to get to them before conditions changed,” Johnson said. “They had to call a mayday.”

Charlotte-Mecklenburg police Chief Johnny Jennings had praise Friday for firefighters who helped bring the 15 workers to safety.