Staff from Northern Ireland’s Agriculture Department have returned to their posts conducting post-Brexit trade checks.
Inspections of animal-based food produce arriving at Belfast and Larne ports were suspended recently amid concerns for the safety of staff.
One police car was parked outside the facility in Belfast Harbour on Wednesday.
One lorry arrived at around 1.45pm on a sailing from Cairnryan and was met by a Border Force officer.
Graffiti expressing opposition to a so-called Irish Sea border had appeared in the Larne area in Co Antrim.
Former Stormont agriculture minister Edwin Poots ordered the suspension of checks shortly before stepping down from the role to receive medical treatment.
His successor Gordon Lyons maintained the position.
The PSNI has since said there was no evidence of “credible threats”.
Sinn Féin and the DUP are at loggerheads over whether the withdrawal of staff was justified at all.
Unionists and loyalists are opposed to post-Brexit arrangements, which they believe threaten the integrity of Northern Ireland’s place in the UK.
