UNDERCOVER PSNI officers have seized three mortars and arrested two men travelling from Donegal to carry out an attack in Derry.
The old Letterkenny Road has been closed for a number of hours as the operation continues and Gardai and the PSNI say it will remain closed overnight.
The van was intercepted in the Brandywell area.
More than 100 families had to be evacuated from their homes as part of an operation which is understood to have involved a cross-Border operation involving Gardai and PSNI officers.
Bomb disposal experts are spending the night examining the mortars.
SDLP politician Pat Ramsey confirmed that he believed the interception of the southern-registered van was a result of an undercover operation.
“One can only say that in the circumstances it would appear to be a good bit of intelligence by the police and that is most welcome,” he said.
“These bombs were in transit somewhere, possibly to cause mayhem, if not murder, in our city.”
Local families were evacuated to a community centre and to Celtic Park.
It’s thought the would-be bombers were traced across the Border during an intelligence-led operation.
Donegal Daily has been told the two men arrested are senior dissident republicans.
A third man was arrested in a follow-up operation early this morning.