The Caernarfon Coastguard helicopter approaches the rescue site. Photo: Aberdyfi SRT

A mother and son were airlifted from a Snowdonia mountain after getting lost in the dark.

Rescuers believed the walkers were uninjured but called in the Coastguard helicopter to the incident on Cadair Idris when it became clear the woman was suffering from a back problem.

Aberdyfi Search and Rescue Team was alerted about 12.45am on Wednesday after the pair called for help.

The 54-year-old woman and her son, 26, both from Kent, had set out the previous day intending to traverse the mountain from Ty Nant via the summit and south ridge to Minffordd.

A team spokesperson said: “At some point after the summit they lost the south ridge path. They continued descending until the terrain became too difficult to continue.

“Speaking to a call-handler they described themselves as ‘unhurt, just lost’, and were able to see what they believed to be the Tal y llyn Lake.

“A team vehicle was deployed to Tal y llyn to show blue lights and look for a response on the hillside.

“A light was spotted on the hillside in Cwm Amarch and an estimated location was calculated. With this information established, a party of team volunteers was deployed up the steep slope to locate the casualties.”

Rescuers planned to walk the pair back down the mountain, but the mother was found to be unable to walk due to the aggravation of a pre-existing back problem. “Given the steep nature of the terrain, assistance from the Coastguard helicopter R936 was requested to help with casualty evacuation,” the team spokesperson said.

The two walkers were winched aboard the aircraft and flown to Ysbyty Gwynedd for further treatment.

The rescue operation ended about 6.30am.