The spokesman said that the flight returned to the airport safely at 1:30 pm local time.
The tweet added: “There are currently no reports of injuries.”
Other police tweets stated that the debris landed in Commons Park and the Northmoor and Red Leaf communities in Broomfield. The city is located about 25 miles north of Denver and 30 miles east of Denver International Airport.
The authorities have not yet determined the exact connection between the two incidents, but the Federal Aviation Administration confirmed in a statement that a Boeing 777-200 safely returned to Denver International Airport after “right engine failure shortly after takeoff.”
The statement said: “The FAA is aware of reports of debris near the flight path of the aircraft.”
CNN has contacted United Airlines for more information.
Broomfield police warned residents that if they see debris in the yard, do not touch or move the debris.
Kieran Cain told CNN that when the plane flew by, they were playing with his children and they heard a loud noise.
Cain told CNN: “We saw it passed, we heard a huge explosion, we raised our heads, and there was black smoke in the sky.”
He said: “The debris is starting to rain, you know, it looks like it is floating down, not very heavy, but actually looking at it now, it is huge metal fragments all over the place.”
He said: “What surprises me is that this kind of aircraft continues to move forward without actually changing its trajectory or doing anything.” “It just keeps moving forward, as if nothing happened.”
Cain said that when the debris fell, he and his children hid under the overhang.
Pete Muntean of CNN contributed to this report.