Rescue teams are asking landowners to search their land on the Comeragh mountains in Co Waterford where a hill runner is missing for almost 24 hours.
The female runner, understood to be in her 40s and from along the Tipperary-Waterford border, was last seen or heard at about 12.45pm on Sunday.
The married woman was due to return from her run along the Coumshingaun Loop trail at 2pm but when her husband did not hear from her he alerted emergency services at 3pm.
The South Eastern Mountain Rescue Association (SEMRA), Search and Rescue Dog Association Ireland, Rescue 117 of the Coast Guard and local gardaí have been involved in the search operation since Sunday.
When last seen the woman was wearing a grey and pink hoody and black trousers and a bobble hat.
Liz Browne, a SEMRA spokesperson said: “We believe that the lady who is missing completed her run successfully but is not a navigator. Heavy cloud descended on the mountain. We are working on the belief that she became disorientated.
“Her phone is still operational as it is ringing out but she could have let it fall and damaged it or she could have lost it unbeknownst to herself.
“We are hoping she was able to find some sort of mountain coverage to keep her warm overnight as it was very cold and damp overnight. She would have been very uncomfortable overnight.”
Ms Browne explained that gardaí and search teams manned all entrances onto the Comeraghs in hope that the missing woman would see the emergency blue flashing lights in the distance.
“We are appealing to all landowners across the area to join the search as they may know of areas where the missing mountain runner could have found shelter. Everyone is doing their best to find her as soon as possible.
“We would ask walkers in the Nire Valley, Rathgormack or Mahon Falls areas to keep an eye out for anything unusual and to contact the gardaí or SEMRA.”
Gardaí are asking hill walkers and farmers in the Coumsinghaun, Mahon Falls, Ballymacarabry and Rathgormack areas to be on alert for any sightings of the woman and to contact gardaí in Tramore on 051-381 333.
The search across the Tipperary and Waterford border, which the Comeraghs straddle, was continued overnight.