A police car was left “unfit for use” after it was attacked by a group of around 35 people who had gathered to cause damage to a home in Kilkeel.
Police arrived at the scene after the group smashed windows and damaged the outside of the house.
There was no sectarian or racial motive behind the attack on the house, police said.
In a separate incident in Newry early on Saturday, the driver of a stolen vehicle attempted to run a police car off the road at high speed.
The car, driven at speeds of more than 100mph and for a time the wrong way down the A1 dual carriageway, almost struck a jogger.
In Kilkeel, the garden of the house was set alight and the police car had two tyres slashed and paint thrown over it.
Officers said they received a report of the incident in the Carn Gardens area after midnight.
“Whilst police were at the address, a crowd of around 35 people gathered and continued to throw items at the house, and at one point set fire to the front garden,” a spokesperson said.
Police say the car has been rendered “unfit for use” PICTURE: PSNI
“The crowd, many of whom were masked, also attacked a police vehicle causing significant damage including two slashed tyres and paint thrown over the bodywork.”
Chief Inspector Adam Ruston added that the police vehicle is now “off the road and will be unavailable for use by local officers to respond to reports from the public for a period of time whilst repairs are carried out”.
“I cannot emphasise enough the foolhardiness of attacking and damaging police vehicles which are needed in order for us to be able to respond to emergencies of all kinds in the local community,” he said.
“And to those involved in attacking the house and the police car, whatever your motivation your actions are unlawful and we are investigating.
“Body worn video has been captured, and will be examined along with all available CCTV and other recorded footage.”
The group slashed two of the tyres and threw paint over the car PICTURE: PSNI
Inspector Ruston said that he would “urge those in the community involved in this morning’s events to examine their actions and realise that taking the law into your own hands is not how we do things in civilised society, nor is attacking the police who are simply doing their job serving the community”.
In Newry, the silver Audi, believed stolen in Drogheda, was spotted by police around 12.40am on Saturday.
The car was driven along the Old Dublin Road and onto the A1 at speeds in excess of 110mph.
Police pursued the vehicle, which continued to carry out dangerous manoeuvres at speed on the dual carriageway.
The Audi then side swiped the police vehicle in an apparent attempt to force it off the carriageway. It continued at high speed.
It was later seen near the Flagstaff roundabout before exiting on to Chancellors Road, where police said it was swerving all over the road and narrowly missed a jogger.
Back on the A1, the car was driven south in the northbound lane before the driver executed a u-turn on the carriageway and then once again leaving the main road.
Police had to stop the pursuit for public safety reasons. The car was later found in the Bessbrook area and has been seized for examination.
In another incident early on Saturday near Dungannon, a white BMW failed to stop for police.
Officers followed the vehicle for a time before losing sight in the vicinity of Tobermeson Road.
The car was then spotted by another police crew in Moy a short time later where it rammed the police vehicle, injuring two officers.
Police tracked the suspect to an address in Maghera. An 18 year old man was arrested on suspicion of a number of driving offences before being released on bail.