What happens when a police patrol takes a wrong turn and drives a couple of miles across the border?
Well, a major "international incident" is sparked, according to a furious politician for the area in the Republic into which the PSNI Land Rover strayed.
The rant by former mayor of Donegal Frank McBrearty – which included calls for a full investigation – were last night laughed off as hysterical.
The police vehicle was pictured in the Co Donegal town of Lifford yesterday after the officers inside lost their bearings.
Realising their mistake, they turned the vehicle round and within minutes were back in Northern Ireland.
End of story? Well, not quite.
Mr McBrearty was scathing in his criticism of the PSNI patrol, claiming their presence in Lifford put lives at risk had dissident republicans have launched an ambush.
"I am calling for an investigation into why they entered our jurisdiction especially with the threat from dissidents," said the independent councillor.
"This is an international incident and should be fully investigated.
"What would have happened if dissidents had have opened fire on the PSNI in broad daylight in Lifford where citizens of our country are going about their daily business?
"This unprofessional behaviour cannot be tolerated by our State."
Lifford is just yards over a bridge from Strabane in Co Tyrone.
A member of the Policing Board last night said Mr McBrearty had blown the incident out of proportion.
"That's a complete overreaction," said DUP MLA Jonathan Craig. "It's just an unfortunate and embarrassing mistake, with the driver seemingly getting lost.
"It shows the good work that is going on in terms of co-operation between the Garda along the border, however, perhaps maps will need to be provided to PSNI drivers to show them just where the border is."
Mr McBrearty was given a picture of the vehicle by a member of Donegal County Council who had been in the area monitoring potential flood threats.
The incident followed several days of intensive police work on both sides of the border to track criminals involved in robberies and burglaries.
When carrying out cross-border investigations PSNI officers can make inquiries in the Republic, provided they are accompanied by Garda officers.
However, neither force has any jurisdiction when operating cross-border.
The PSNI said it was looking into the error.
"A police patrol inadvertently crossed the border into Lifford today for a short time," a PSNI spokesman said.
"On realising his error the driver turned at the next available roundabout. Police have made An Garda Siochana aware of the incident."