Offices belonging to anti-Brexit Alliance Party politicians in Northern Ireland have been daubed with graffiti.

North Down MP Stephen Farry and Strangford Assembly member Kellie Armstrong were targeted.

The vandalism included “RIP Good Friday Agreement” in a reference to the 1998 peace deal which largely ended decades of conflict.

Alliance leader Naomi Long said: “This campaign of intimidation against the Alliance Party is as futile as it is despicable.

“We’re serving the community, seeking solutions to the problems others caused.

“We will not be deflected from that by bomb hoaxes and graffiti.”

Offices belonging to DUP Strangford MP Jim Shannon and Stormont Education Minister Peter Weir in Newtownards were also targeted with graffiti.

DUP Assembly member for Newry and Armagh William Irwin said police had told him of a threat against him.

There were calls for cool heads and language to be tempered in the Northern Ireland Assembly following the threats against staff at Belfast and Larne ports.

Alliance representative Stewart Dickson said they were unacceptable.

Mr Irwin urged those behind the “sinister activity” to desist immediately.

He was contacted by police on Saturday and informed of “social media misinformation” and a threat against him.

Sinn Fein representative Linda Dillon reminded those speaking at Stormont to watch their tone.

“We need to have cool heads, we need to temper our language, we need to know that the tone that we set in this place is what will happen outside, and for us not to take full responsibility for that is disingenuous,” she said.

Nationalist SDLP representative Patsy McGlone branded the intimidation despicable.

Ulster Unionist Roy Beggs, who represents the area covering Larne Port, said there should be no place for violence or the threat of violence.

He called for clear reflection on the Northern Ireland Protocol, describing what has been introduced as “not proportionate or reasonable”.

“There is growing discontent in the unionist community and I can only see that growing as more and more people recognise that they have difficulty buying seeds, plants, small parcels, not being to get goods to delivered to them,” he said.

“So there needs to be adjustment.”