Video (00:33) : Firefighters were forced from the building's interior in the wake a second-floor collapse.

A morning fire devoured a historic block along W. Broadway in Minneapolis, closing a section of the North Side’s main retail thoroughfare and displacing more than a dozen residents before it was extinguished Wednesday.

Four people were hospitalized with injuries stemming from the fire, which began sometime after 8 a.m. behind an Unbank check-cashing and loan business at 913 W. Broadway. It spread quickly through at least three other buildings, including Brix, a longtime grocery store, and the headquarters of Neighborhoods Organizing for Change (NOC).

It took more than three hours to contain the fire. The cause has not been determined.

At one point, fire crews were pushed back when the second floor nearly collapsed on them. No firefighters were injured, said Assistant Fire Chief Chérie A. Penn.

Fire Chief John Fruetel said that investigators would work to determine the structural safety of the building and adjoining structures. Several buildings, if not all, are likely to have to be torn down, he said.

The row of buildings, built between 1893 and 1910, is one of the last historic blocks on the North Side.

Map: Map of the north Minneapolis block where businesses burned Wednesday Map: Map of the north Minneapolis block where businesses burned Wednesday

A line of onlookers outside the police tape stretched around the block, their view sometimes obscured by plumes of dark smoke that hovered over the area most of the morning.

NOC Director Anthony Newby watched as firefighters put out hot spots in the space that used to be the organization’s headquarters. He said that no one was in the office when the fire broke out.

Newby said “the whole backside was lit up” when he show-ed up for work that morning.

“We’ll be able to rebuild. This is a movement. We’re not tied to any specific address,” said Newby, who spent the morning planning an online fundraising drive to raise $20,000 for residents affected by the fire.

Resident Penny Hopkins watched the first fire engines pull up to the scene shortly before 9 a.m. from her apartment kitty-corner from the fire. “This whole block is gone,” Hopkins said hours later, as she surveyed the damage. “It’s a demolition job now.”