Ten people are in hospital after shots were fired overnight in the Moss Side area of Manchester.
Two children are among those with “pellet-type wounds” and one man is in a serious but stable condition with leg injuries, police have said.
The nine people with pellet injuries are expected to leave hospital later today.
“A large number” of armed and unarmed officers were called to Claremont Road at about 2.30am.
Manchester Caribbean Carnival had brought large groups of people to the area, with several after-parties understood to have taken place in Claremont Road.
The carnival – which this year is celebrating the 70th anniversary of the Windrush generation – will go ahead as planned on Sunday.
Festival organiser Mike Bisson called the shooting “an isolated incident” and said it had “nothing to do with the carnival”.
Chief Superintendent Wasim Chaudhry, from Greater Manchester Police, called the shooting “a reckless act that could have had devastating consequences”.
He added: “Guns have no place on our streets and we want to assure you we are doing everything we can to find the person or people responsible.”
The area of the shooting has been cordoned off
Moss Side is about two miles out of Manchester city centre Claremont Road runs for about two miles through Moss Side.
The area has numerous gang territories and has long had problems connected with drugs and gun violence.
Footage reportedly showing the aftermath of the incident was posted on Twitter, with the caption: “Shooting at Manchester Moss Side post carnival street party”.
The dark video appears to show a panicked group of people being helped by police.
As a voice cries out, shouts of “move” can be heard, while another voice asks “can you hear me?”.
“Give us some space guys” can also be heard in the background, while another voice says, “are you dumb?” as the camera pans around.
Detective Superintendent Debbie Dooley said: “We currently have a number of people in hospital all being treated for different injuries but thankfully most do not appear to be life-threatening at this time.
“Officers are trying to establish exactly where this incident took place and who is responsible for such a dangerous attack.”
Wayne Everett, a local DJ who attended the carnival, told Sky News: “The atmosphere was nice, but it’s Moss Side isn’t it? You just don’t know what can happen. It seemed like there was a general understanding over the last few years that everyone would just behave themselves.”
Going on to describe Moss Side as “a volatile area”, he said police should not have allowed the carnival to go ahead.
He said: “It’s only a matter of time. You can’t have thousands of youths in the area in the early hours of the morning just doing what they want. It’s common sense…
“As someone from the area, I decided to come down and see this thing, because 10 people is a major thing in Manchester.”
Police say they are looking at CCTV to find out how events unfolded
Officers and forensic experts are now on the scene.
Superintendent Dooley said: “The area is being searched and examined while we are also trying to speak to as many people as possible and are reviewing CCTV to get all the facts.”
Extra police have been sent to the area, which is around two miles south of Manchester city centre.