A senior police officer has stood by the assessment that loyalist paramilitaries were not behind alleged threats to port staff in Northern Ireland earlier this year.

A Stormont committee is examining the circumstances around the withdrawal by Mid and East Antrim Council of staff carrying out post-Brexit checks after allegations of loyalist intimidation.

Department of Agriculture staff at Larne port were also withdrawn at the start of February.

Threatening graffiti appeared in the area following the UK’s departure from the EU which, under the terms of Northern Ireland Protocol, saw additional checks on good arriving into the region from Great Britain.

There were also allegations that the number plates of staff vehicles were recorded and negative social media commentary.

Police later said there was nothing to substantiate claims of loyalist paramilitary involvement and no evidence of “credible threats” to staff.

Last month Mid and East Antrim mayor Peter Johnston (DUP) and chief executive Anne Donaghy told the Agriculture Committee they stood by the decision to withdraw staff on February 1, saying staff safety was their priority.

Appearing before the committee on Thursday, Assistant Chief Constable Mark McEwan said the intelligence assessment was that “loyalist paramilitaries were not behind the graffiti” and “were not intent in taking part in driving any of the action around portal activities”.

“That remains the case today,” he told MLAs.

Alliance MLA John Blair said Ms Donaghy had written to the UK Government’s Cabinet Office around the time the staff were withdrawn.

He said she wrote that she was “aware of the involvement of paramilitary groups in recent protests at Larne port”.

Mr McEwan said police have “consistently given the threat assessment that we do not assess that loyalist paramilitaries are behind this”.