Mass brawls broke out among groups of young people in an Edinburgh park, with the police federation saying an officer was injured in the violence.
Hundreds gathered in the Meadows on Saturday afternoon as the city enjoyed warm weather and the stay-at-home order came to an end.
Footage shared on social media showed groups of young men fighting each other, with one being struck by a bottle.
Police officers can also be seen tackling people to the ground in the clips.
David Hamilton, chairman of the Scottish Police Federation, accused politicians of “offloading predictable problems” onto officers.
He said: “Police officers didn’t write these health regulations but for the last year we have been asked to enforce them for the protection of all.
“Public hostilities towards the restrictions were foreseeable and have been growing for some time.
“They have increasingly culminated with some in our society taking out their anger and frustrations on police officers.
“Yesterday in Edinburgh, one of our members was hospitalised with a facial injury, and countless other unvaccinated officers were put at risk, for simply doing their jobs to keep others safe.
“It is simply not good enough that politicians have offloaded these predictable problems onto police officers, especially when they have failed in their responsibility to protect and support those of whom they have asked so much.”
The MP for Edinburgh South, Ian Murray, said police and the council should come up with an action plan to deal with trouble on the Meadows and the mess left behind from large gatherings.
He tweeted: “It’s a huge thank you to all the volunteers & council staff who cleaned up the Meadows again last night.
“We need an action plan from the council, police, govt, retailers to resolve the mess, violence, residential streets being used as a toilet & significant impact on local area.”
It comes after Scotland’s chief medical officer warned that people coming together in large groups risked a resurgence in coronavirus cases.
On Thursday, he said progress in suppressing the virus had been “fragile”.
Scotland’s stay-at-home order came to an end on Friday as part of the planned easing of lockdown, being replaced with a “stay local” rule.
A senior police officer said some of the thousands who gathered on the Meadows were intent on disorder.
Chief Inspector Sarah Taylor said: “We are aware of the extent of the disorder seen in the Meadows this weekend and we absolutely condemn this.
“Officers were called to a number of incidents over the course of the day and responded quickly and professionally in the face of some blatant anti-social behaviour.
“Hundreds of people were moved on or dispersed from the area.
“Three people have so far been charged in connection with anti-social behaviour and a serious assault, and we are working to trace others involved in various incidents.
“In particular, we’re eager for anyone who saw a 22-year-old man being attacked around 7.30pm in the Middle Meadow Walk area and also a 17-year-old man being seriously injured in the park around 6.40pm, to come forward.
“Anyone who witnessed these incidents, who has seen information online or has footage which may be relevant is asked to contact Police Scotland on 101, quoting incident 1635 of 3 April, 2021. Information can also be passed anonymously to the independent charity Crimestoppers on 0800 555 111.
“Be assured that there will be a continued police presence at the Meadows over Easter and the coming weekends, as a minimum.
“We’ve been working with the council and are committed to tackling these issues together, both in the immediate future and long-term. There will be zero tolerance.”
Diane Gray, who lives in the area, said the Meadows has been very busy on sunny days with “hordes of young people congregating”.
“I don’t blame them for wanting to meet up, just wish they would be more responsible,” she said.
Ms Gray said there had been problems with litter, including human waste, broken glass and “drug paraphernalia”.
“Personally I am older/restricted mobility and I keep well away on days when it’s busy because it doesn’t feel safe,” she added.