A POLICE chief last night urged a runaway schoolgirl and her 23-year-old cousin to give themselves up.

Detective Superintendent Shane Sellers made the plea as it was confirmed that the hunt for the missing 14-year-old Margaret O'Brien was concentrating in the Republic of Ireland, with the active help of the Garda - and police in Northern Ireland.

The teenager vanished from her Thornaby home on Good Friday, with her cousin James Patrick O'Brien, 23.

Det Supt Sellars said: "My message to Margaret and Mr O'Brien is simple: Go to your nearest police station and give yourself up. You cannot continue as you are.

"It is only a matter of time before you are found and it would be far better for all concerned if you handed yourselves in to the police because we will not give up our search."

He insisted there would be no let up in their hunt for the couple.

"We believe this couple are still in southern Ireland and we are appealing to people there to be our eyes and ears to help us locate Margaret," Det Supt Sellars said.

"We want her back safe and sound with her family who are distraught over her disappearance.

"It is now six days since she vanished from her home in Thornaby.

"Thanks to the tremendous response from the public and media we have managed to trace their movements from the Cleveland area up to Scotland and across to Northern Ireland."

The police chief said: "We have a team of officers currently in Scotland collating evidence and collecting statements from people who have spotted this couple.

"We have also received excellent co-operation from the Scottish Police, Police Service of Northern Ireland and the Garda, who are currently carrying out inquiries in Ireland on our behalf.

Maverick bishop Pat Buckley said the couple had approached him in Larne on Monday and asked him to marry them, but he refused because Margaret is too young.

Mr Buckley, who broke ranks with the Roman Catholic church, said: "I think it is a mature love rather than a sinister abduction.''