Police were attacked with petrol bombs and missiles as they carried out searches targeting dissident republicans in Derry.
Officers were targeted after finding a suspicious object while carrying out searches for New IRA bomb-making equipment in the Creggan Heights area of the city.
The Police Service of Northern Ireland later confirmed the object was a “viable explosive device”. Having evacuated some 15 homes late on Monday night, they tweeted soon after 5.00 am that the device had been made safe and residents could return to their dwellings.
Young people engaged in the disorder in Derry’s Creggan estate sustained burn injuries during the violence on Monday night, the PSNI said.
The police searches were launched after a dissident republican mortar bomb was recovered in Strabane, Co Tyrone on Saturday.
The mortar, which was positioned close to a family home, was aimed at the town’s police station.
It was the seventh attempted murder bid against the security forces in Northern Ireland this year.
Journalist Lyra McKee, 29, was murdered by the New IRA in the same Creggan Heights area in April as she observed dissident rioting.
PSNI Assistant Chief Constable Mark Hamilton described the operation around the suspicious object as “complex” as he condemned those indulging in disorder.
“The focus of this operation is ensuring the people of Creggan are safe however it is concerning to see significant numbers of young people on the streets, late into the night, throwing petrol bombs and other missiles at officers in the area,” he said late on Monday night.
“The reality is this type of disorder contributes to the complexity of the policing operation and presents a real risk of injury to those involved.
“Already we have seen two incidents this evening where young people have sustained burn injuries as result of engaging in disorder.
“I would reiterate our appeal for those young people to return home and remove themselves from the situation.
“We are grateful for the support of community representatives in helping to reduce tensions and providing space for officers to carry out the necessary work to ensure this object does not present a risk to the people of Creggan.”
Sinn Fein Assembly member Karen Mullan said the security alert had caused significant disruption to local residents. She also condemned the disorder.
“There is absolutely no justification for the actions which serve no purpose other than to put people at risk of serious harm and make the situation worse for local residents trying to get on with their lives, and they should stop now,” she said.
SDLP leader Colum Eastwood appealed for calm in the area.
“Police officers came into Creggan today to take bombs out of the hands of those who are trying to murder innocent people in our communities, like those responsible for the mortar in Strabane,” the Foyle MLA said on Monday night.
“The brutal and sustained attack that officers have come under while trying to make our community safe is disgusting. Young people in this community are being manipulated and are risking their futures as a result. I would urge parents to contact their children and take them out of harm’s way.
“People in this community will not be held to ransom by those who want to hold us all back.”