The main Belfast to Dublin railway line remains closed between Newry and Dundalk due to security alerts.
Passengers are being bussed between the stations
The dissident republican Real IRA said on Friday it had left two devices on the line.
A police spokesman said the Newry by-pass is also likely to remain closed for much of Sunday due to a security alert.
The road is closed in both directions between the Five Ways roundabout and the Fork Hill Road roundabout.
The Real IRA also claimed responsibility for the firebomb attacks on stores in Newry earlier in the week.
The SDLP mayor of Newry and Mourne, Michael Carr, said there "was no support in the community for this sort of activity".
"The people that are being harmed are the people of Newry and Mourne, the people on the ground, the people trying to earn a crust of bread," he said.
"There is no support and we are saying to them loudly and clearly: 'go away, we don't need this'."
Firebombs destroyed JJB Sports and CarpetRight stores in the town whilst a TK Maxx store and MFI outlet were among those badly damaged on Wednesday.
The attacks are estimated to have caused damage worth hundreds of thousands of pounds.