Petrol bombs were thrown at police as up to 50 masked people were involved in disorder in Co Derry on Monday night.
Officers were called to the Waterside following reports that a large group of between 40 and 50 people had gathered in the area at around 7.30pm.
Police said the group, described as a mixture of older and younger people, was reported to be heading towards playing fields at Knockwellan Park, with some of those present believed to be carrying weapons.
Officers responded to the scene and those gathered initially dispersed in different directions, but remained in the general area.
Police stayed in the vicinity and engaged with community representatives in an effort to establish what was happening and defuse tensions.
However, the situation subsequently escalated when petrol bombs were thrown at officers.
A road was also blocked at the junction of Trench Road and Strabane Old Road using wheelie bins and other items.
Police said calm had been restored by around 10.30pm and no further incidents were reported, although officers remained in the area carrying out high-visibility patrols.
No police officers were injured during the disorder.
Derry City and Strabane Superintendent Sinead McIldowney described the scenes as “absolutely disgraceful” and said police believe the trouble had been orchestrated.
“We believe this disorder was orchestrated, which is shameful as many of those involved have been described as young people. They are being used and exploited, and that is reprehensible,” she said.
Addressing adults who were present, Supt McIldowney said they were responsible for placing young people in danger, both physically and by putting them at risk of acquiring a criminal record.
She added that the disorder was not reflective of the wider community or the work being carried out by people across the city.
“Last night’s disorder is not welcomed or wanted by any right thinking person, and shows the lack of respect by those involved for the community,” she said.
Meanwhile, SDLP Foyle MP Colum Eastwood has said there is “real concern” in the city after the disorder on Monday night.
“The sight of masked individuals armed with weapons gathering in our city is extremely sinister and has caused real concern in the local area,” he said.
“Nobody wants to see scenes like this on our streets and it’s extremely fortunate that nobody was seriously hurt as a result of this disorder.
“I’m extremely concerned at reports that large numbers of young people were involved and that police believe the disorder may have been orchestrated in an interface area.
“Any young person getting involved in this type of activity is putting their own future at risk, and the adults involved need to take a long hard look at themselves for putting young people and the wider community in danger.
“I condemn the attacks on police and the blocking of roads during this incident, and I welcome the police and community response that helped prevent the situation from escalating further. Anyone with information should come forward to police.”
Police have now increased their presence in the area, with Supt McIldowney acknowledging the incident would have been “very unsettling and frightening” for local residents.
The disorder has also prompted a strong reaction online after footage and details of the incident were widely shared.
Writing beneath one viral social media post, one person said: “These idiots in no way represent Top of the Hill. A community on the rise with so many positives, always a small element trying to drag it down.”
An investigation into the disorder is now underway.
Police have appealed for anyone with information, including dash-cam, CCTV or other footage, to contact officers on 101 quoting reference 1488 of September 7, 2026.