Two men are in custody in the North after they allegedly forced a taxi-driver to drive them across the Border as gardaí pursued them from Castleblayney, Co Monaghan, last night.
A Garda spokeswoman said gardaí in Castleblayney searched a house at Ard na Lorgan at about 8.20pm.
"A firearm was recovered and a 38-year-old woman was arrested and is being detained at Castlblayney Garda station under section 30 of the Offences Against the State Act," she said.
In what the spokeswoman described as a follow-up operation, gardaí tried to arrest two men, aged 19 and 39, in a taxi at Ard na Lorgan at 8.30pm.
"In the course of the operation, the men threatened gardaí with what is believed to have been a firearm and then forced the taxi-driver to drive off," said the spokeswoman.
Gardaí pursued the taxi.
Two men were later arrested by the PSNI in Keady, Co Armagh.