A bomb was tonight defused on the Northern railway line in South Belfast, bringing to an end a three-day security operation.
RUC Chief Insp Tom Haylett condemned those who had left the device at Finaghy Halt, saying they could have caused death or serious injury.
He said a detonator and other substances had been removed for forensic analysis.
"This has the hallmarks of an explosive device which, had it exploded, could have caused a serious risk to life and property," he said.
The North’s First Minister, Mr David Trimble, today challenged Sinn Féin president Mr Gerry Adams to condemn the bomb alerts which have left the North's rail network in chaos.
Mr Trimble said the violence and attacks - there have already been 33 alerts on rail services this year - were clearly organised by republicans, including those linked to Sinn Féin.
He said the violence was deplorable and added: "I would dearly love to see the leadership of the republican movement, especially Sinn Féin President Gerry Adams, showing leadership on this issue.
"On the ground it is not always easy to tell the difference between mainstream republicans and dissident republicans and there is a strong suspicion that mainstream republicans have also been involved in violent acts in recent days.
"That is why I think there is a particular onus on Mr Adams and his colleagues to make it clear where they do stand on the Good Friday Agreement, because I don't see much evidence of them in recent weeks and months trying to make it work."
PA