Police hold suspect over missing Karen
Investigators are following 'definite line of inquiry' Divers, forensic officers trawl farmland and buildings
Hopes of finding missing student Karen Buckley alive faded as police moved their search to woodland outside of Glasgow.
Police Scotland said they were "following a definite line of enquiry" after 21-year-old Alexander Pacteau was detained in connection with her disappearance.
He was seen talking to Karen in the early hours of Sunday morning before the student from Cork vanished.
In the hours after her disappearance, Mr Pacteau told police he drove Karen to his apartment on Dorchester Avenue. However, he said she left only hours later at 4am to walk home.
Karen has not been seen for almost four days, as police divers, a helicopter crew and search dogs searched areas throughout Glasgow city.
Last night hundreds of officers moved to cordon off land near High Craigton farm on a rural road, between Glasgow and Drymen.
Quad bikes and fire engines also moved in to assist in the search of the rugged landscape north of Glasgow.
Teams have been scouring Dawsholm Park in the city, where Karen's handbag was found on Monday.
They also searched the nearby flat in Dorchester Avenue where the student was reportedly last seen.
Forensic teams could be seen sorting through rubbish bins at the rear of the property.
In a desperate plea on Monday, her mother Marian Buckley (61) said: ''We just want Karen home safely, we are desperate. She is our only daughter, we love her dearly."
One of her older brothers Kieran (28) has travelled from Sydney to be with his parents.
Police said the investigation into Karen's disappearance remained a missing person inquiry last night.
Police were allowed to detain Mr Pacteau for up to 12 hours.
Under Scottish law, police can detain someone who they believe has committed a crime. This may, in certain circumstances, be extended by a further 12 hours.
At the end of that period, they must be arrested or released.
Detective Superintendent Jim Kerr, who is leading the hunt, said it was his "absolute priority" to find Karen.