Four civilians and two firefighters sustained minor injuries Wednesday morning when part of a construction crane in Manhattan caught fire and plummeted from the top of a skyscraper to the street below, New York City authorities said.

Firefighters were already en route at 7:25 a.m. to what became a five-alarm fire when the crane collapsed atop a 45-story building under construction on 10th Avenue in the Hudson Yards area of Manhattan, FDNY First Deputy Commissioner Joseph Pfeifer told assembled media. All of those who were injured, including a firefighter experiencing chest pains, were outside when the crane fell, Pfeifer said.

"We were extremely, extremely lucky this morning," New York City Mayor Eric Adams said at the news briefing. "As you can see from the street, this could have been much worse."

Skyscraper planned at 550 10th Ave., where crane collapsed

More than 200 firefighters and medics responded to the area, where Pfeifer said they evacuated surrounding buildings and stretched hose lines to the top floors of nearby skyscrapers to battle the blaze. Drone footage appeared to show that most of the fire had been extinguished by around 9:30 a.m. local time, he said.

The skyscraper at 550 10th Ave. is intended to become a 54-story mixed-used building, said Jimmy Oddo, commissioner of the New York City Department of Buildings. Oddo said at the news briefing that his office will conduct an investigation, and an independent assessment will be commissioned as well.

"It's my job and our agency's job to find out what happened here," Oddo said.

Crane was carrying concrete

A preliminary investigation revealed that the crane's operator was lifting 16 tons of concrete when the operator noticed that a fire had started in the engine compartment of the crane. The fire heated the crane's cable, weakening it to the point that it lost strength, causing it to collapse, Pfeifer said.

Unable to contain the blaze, the operator had no choice but to exit the crane and get to safety, he added. As the top part of the crane fell, it struck a building across the street at 555 10th Ave.

Videos show crane collapse, fire

The crane can be seen ablaze in multiple videos captured by bystanders and posted to Twitter before it and the load of concrete detach, slam into the neighboring building, and fall to the street below.

One video posted on Twitter by user @jimmy_farring shows the crane on fire before it breaks loose and crashes into a skyscraper across the street and onto the ground, sending pedestrians fleeing the area.

(Editor's note: Video contains profanity).

In another video shared on Twitter by podcaster Paula Pant, black smoke could be seen billowing into the sky after the top of the crane detached and fell.

Surrounding streets were closed to traffic, but some reopened around 9:30 a.m., according to a tweet from the New York City Police Department. However, 10th Avenue remained closed between 34th and 42nd streets as of Wednesday morning, police said.

The location on Manhattan’s west side is near the Port Authority Bus Terminal and an entrance to the Lincoln Tunnel, which carries auto traffic to and from New Jersey under the Hudson River.

Contributing: Associated Press.

Eric Lagatta covers breaking and trending news for USA TODAY. Reach him at [email protected] and follow him on Twitter @EricLagatta.