A PSNI officer was allegedly kicked in the face after police moved in to disperse a crowd of more than 200 youths that had gathered at Ballyholme beach on Friday night.
Police said officers came under attack from sections of the crowd during which the officer was injured.
Four teenagers were arrested following the incident and a 17-year-old male has been charged with number of offences, including assault on police, and is expected to appear at Newtownards Youth Court on June 23.
Two others, a female aged 18 and a male (16) have been released pending a report to the Public Prosecution Service, while a 15-year-old male remains in custody.
PSNI Assistant Chief Constable Alan Todd said that, while he understands people want to go out and make the most of the good weather, police have to play their role in helping to stop the spread of coronavirus.
"The latest data available shows that the ‘R-number’, which was flattening/falling, has actually increased again as restrictions have been eased," he said.
"This means that every one of us needs to make informed and sensible decisions about our conduct over the coming days to ensure that we are protecting our own health and the health of others."
Police have increased their patrols over the weekend, particularly around beauty and tourist spots, focusing on tackling large crowds ignoring social distancing rules, alcohol consumption in public places and road safety.
“The public should be well aware of the advice from our public health partners and the Government about social distancing and movement and, on that basis, we would encourage people not to drive to local beauty spots or popular destinations for their daily exercise as others may have the same idea and social distancing may not be achievable," ACC Todd added.
“Each and every one of us has a personal responsibility to follow the NI Executive regulations and do everything we can to stop the spread of Covid-19.”
On Friday, National Trust rangers spent three hours filling 11 bags of rubbish at Bloody Bridge near the Mourne Mountains in Co Down.
Bloody Bridge is a popular starting point for hikes into the mountains as well as coastal strolls.
A fire was also set which had to be attended by fire crews, the National Trust said.
It added: "These beauty spots deserve more of your respect, so please take away the rubbish you bring with you, and with this hot weather, use common sense and don't bring BBQs with you to protect the fragile habitats we work hard to look after."