Police officers were injured as they attempted to disperse a large group of people in Leeds.
West Yorkshire Police had attended reports of a large gathering in the Potternewton Park area on Sunday, where five officers received minor injuries.
The force said it had closed down other gatherings which breached coronavirus restrictions and seized DJ equipment.
A city-wide dispersal order was in force throughout the Bank Holiday weekend.
The order allowed officers to ask people to leave a specified area and not to return for 48 hours or face arrest. It also authorised the police to confiscate items such as sound systems or other music equipment.
It was used alongside new tougher penalties introduced by the government enabling organisers of illegal gatherings of more than 30 people to be fined up to £10,000.
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Major events, including Leeds Festival, Leeds West Indian Carnival and the Black Music Festival, were due to take place over the weekend but were postponed due to the coronavirus pandemic.
Assistant Chief Constable Tim Kingsman said: “I understand people being frustrated at not being able to enjoy themselves in the same way as they might have done in previous years.
“But major events would not only have breached restrictions – they could have put people’s health at risk too.”
He said the vast majority of residents had complied with the restrictions.
Source: BBC News