Coast searched for missing Ballycastle woman Karen Coyles
Two dive teams are to join in the search for missing Ballycastle woman Karen Coyles.
Ms Coyles, 47, has not been seen since Sunday night. Her car was found outside the camogie club in Ballycastle at about 07:45 BST on Monday.
Police investigating her disappearance are focusing on a section of the north Antrim coastline.
Dundalk Sub-Aqua Search and Rescue and the Mourne Underwater Search teams will scour an area below cliffs.
The ground search is continuing with both the community and police rescue teams working together.
It is focused on a one and a half mile area, including a small part of the coast which has been cordoned off.
Police said they were following a definite line of inquiry.
They have appealed to anyone who may have seen Ms Coyles walking through Ballycastle on Sunday night or Monday morning to contact them.
Area Commander for Moyle, Chief Inspector Sean Fitzpatrick said: "Extensive searches of the Ballycastle area have been carried out by police officers, sniffer dogs, helicopter and the local community.
"We are now concentrating our resources around the coastline and are following a specific line of enquiry. The search operation is continually reviewed by the senior investigating police officer and partner agencies."
Family and friends are becoming increasingly concerned for her safety.
They first realised there was something wrong when she did not turn up for work at the University of Ulster.
The alarm was raised and the coastguard, police helicopter and the local community joined in the hunt. More than 100 people are involved.
Divers examined the bottom of a cliff face on Wednesday after a search and rescue dog had indicated there were some clues.