Police in the North are investigating after a bus was hijacked and set on fire in Co Down this morning.
It happened on Abbot Drive in Newtownards at around 6:30 am.
Officers say two masked men boarded the bus and poured fuel over it before setting it alight.
The driver was not injured, but police say he has been left badly shaken by the incident.
Allison Morris, Belfast Telegraph crime correspondent, told The Pat Kenny Show the bus driver was told it was linked to the Irish Sea border.
She explained: "We're being told as he was being ordered off the bus, he was told it was in relation to the Northern Ireland Protocol.
"Today is November 1st... Jeffrey Donaldson said earlier this year that if there was no progress in the protocol by the end of October he would pull his ministers out of the Northern Ireland Assembly. I'm assuming the date is relevant to that."
She said the fear is this could be the start of another series of riots and disturbances, and more vehicles could be set on fire in the coming days.
She said the early indications - including the location of the hijacking - suggest loyalists were involved.
It follows the riots and violent protests in Belfast and elsewhere in Northern Ireland earlier this year.
Condemning today's incident, DUP leader Jeffrey Donaldson says terrorism will do nothing to secure the removal of the Northern Ireland protocol.
He said: "There was never any justification for masked gunmen on the streets of Northern Ireland and there never will be.
"That is the roadmap to securing removal of the Irish Sea border. Those engaging in thuggery only undermine these efforts and cement the Protocol more firmly in place."