NBC-- Large metal parts from a United Airlines airplane fell from the sky and landed in a neighborhood outside Denver, Colorado, authorities said Saturday.
While the debris caused some property damages, Broomfield police said they haven't received reports of injuries.
United Airlines said in a statement that "Flight 328 from Denver to Honolulu experienced an engine failure shortly after departure, returned safely to Denver and was met by emergency crews as a precaution."
United said there were no reported injuries onboard, and the plane was carrying 231 passengers and 10 crew.
The plane's pilot told air traffic control that they were experiencing an "engine failure" after reporting a "heavy mayday."
Emergency medical services were sent toward the airport at the time of the incident after receiving a call of a possible engine fire.
Broomfield police urged people who find any plane debris to not move it or touch it.
The National Transportation Safety Board "wants all debris to remain in place for investigation," the department said in a tweet.
Kieran Cain, 46, of Broomfield, was playing basketball at a nearby elementary school with his kids when he saw the debris falling from the sky. They quickly took shelter under a nearby gazebo when they “watched the stuff fall down,” he said, “all while keeping an eye on the giant metal ring."
"We heard a gigantic boom and, as we did that, we saw a huge puff of smoke and then stuff started falling out of the sky," he said. "That's when I called 911."
Cain then decided to driver over to where the debris appeared to be falling. "On the way, there was just debris all over the streets," he said.