Police and fire crews have been attacked with missiles following trouble in north Belfast.
Masonry, bricks and bottles were thrown at officers responding to disorder near the New Lodge area on Friday night.
Police said a young boy was reportedly assaulted when rival groups were involved in an altercation.
A 15-year-old boy was arrested on suspicion of common assault and riotous behaviour. He has since been released and cautioned.
The police said it was extremely disappointing that officers had to deal with the actions of individuals who showed a complete disregard for the community.
CCTV footage is being reviewed to identify those involved.
Supt David Moore said they were called to the junction of North Queen Street and Duncairn Gardens, shortly before 20:00 BST.
"Upon arrival of police in Spamount Street, officers had both masonry and other missiles thrown at them by a group of youths," he said.
"Youths then set large, industrial bins alight in the area to attempt to block the road.
"Northern Ireland Fire and Rescue Service attended the scene and had bricks and bottles thrown at them during the incident.
"Damage was also reported to the grounds of a nearby nursery school by youths involved in the disorder."
Supt Moore said no officer or firefighter was injured but that damage was caused to police vehicles, including wing mirrors and a smashed windscreen.
"For officers and colleagues from Northern Ireland Fire and Rescue Service to come under attack in trying to keep people safe, means that vital resources are being removed from public use when they could be better utilised elsewhere," he added.
"We will continue to work alongside local representatives and partner agencies, but it is disappointing that some people continue to disregard our repeated warnings.
"Those people who choose to engage in criminal and anti-social behaviour must understand it is unacceptable and must stop.
"People have a right to live in peace and to feel safe in their communities."
Sinn Féin councillor JJ Magee said Friday night was "very bad for the residents of the New Lodge area".
He said while a small amount of people were involved, they were "causing havoc" for residents.
"This has been ongoing for months now, almost on a nightly basis," he said.
"The residents have been getting tortured by young people who come from all over Belfast to this site where they then create trouble.
"People have tried to move these young people on, but the abuse and the stick and then the threats that they take from these young people is scary."