Ten people are in the hospital after a "shooting" in the Moss Side area of Manchester, in northern England.
Armed police officers from Greater Manchester were called to Claremont Road at 2:30 a.m. (local time) on Sunday and discovered that several people had been injured.
"Nine people went to the hospital, including two children, with pellet-like injuries that are not considered serious," said a statement from Greater Manchester police.
"A tenth person, a man, remains in a stable but serious condition at the hospital with leg injuries."
Police said they hoped that less severely injured victims would begin to leave the hospital during the course of the day.
"This was a reckless act that could have had devastating consequences with families and friends who lost their loved ones," said Superintendent Wasim Chaudhry.
He said the police were looking for the person or persons responsible.
The area was occupied after the Caribbean carnival, which ended a few hours earlier, they added.
The Caribbean Carnival is a street festival, which includes dance, music and costumes.
The officers remain at the scene of the shooting and the police are working to identify those involved.
The images, reportedly taken during the shooting, were posted on Twitter. The video shows people in panic with the police.
A voice can be heard screaming "move".
Moss Side is in the south of Manchester, not far from the center of the city.