Police in Northern Ireland investigating the murder of Constable Ronan Kerr have arrested a man in Scotland over a significant arms find.
Mr Kerr, 25, was killed when a car bomb exploded in Omagh on Saturday.
Police have said the arrest is linked to a weapons find in the Coalisland area of east Tyrone.
The weapons included four rifles, detonators, component parts for rocket launchers, incendiary bombs and explosives, possibly Semtex.
Speaking at a news conference at police headquarters in Belfast, Assistant Chief Constable Drew Harris said the man was arrested in Renton, West Dunbartonshire, and brought back to Northern Ireland.
He said the weapons were found on Tuesday night inside stolen cars in a garage at Mountjoy Road in Coalisland.
"Everyone in Northern Ireland is very much safer today because these munitions have been taken out of circulation," he said.
ACC Harris said the find was "the most significant in recent years".
The arms found were:
•Four Kalashnikov rifles
•Six loaded ammunition magazines
•Timer power units
•Components for rocket launchers and other explosive devices
•Quantity of explosives, possibly Semtex
Police said the items were being "fast-tracked for forensic examination" and formed one line of inquiry in the Ronan Kerr murder investigation.
"A man has been arrested in Dunbartonshire in Scotland in connection with the find of weapons at Coalisland," ACC Harris said.
"This 26-year-old suspect is being brought back to Northern Ireland for questioning. Colleagues from Strathclyde Police assisted PSNI detectives in the arrest operation.
"The seizure was made in a garage unit on the Mountjoy Road. Inside the unit, police officers uncovered a number of stolen vehicles and inside those vehicles, a significant amount of arms and munitions," he said.
"This investigation into Ronan's murder will continue in the coming days and weeks with the same determination and professionalism which resulted in last night's discovery."
Assistant Chief Constable George Hamilton from Strathclyde Police said a search had been carried out in connection with the arrest in Renton, but nothing had been found.
"I would like to reassure people in West Dunbartonshire and across the Strathclyde Police area that there is nothing to suggest there is any increased threat to people here in connection with this arrest," he said.
Anne Murphy lives near to where the explosives were found in County Tyrone and said there had been a major police operation.
"It really took off about six o'clock on Tuesday evening," she said.
"I've never seen anything like it before, in the amount of resources that have been in the area.
"There have been jeeps, there have been mini-buses, large vans, with possibly forensic vehicles included.
"They've been here continuously, manning the place. The area's been blocked off."