A search has been launched for a Trinity College professor who has gone missing while making his descent from Mount Everest.
Climber Seamus Lawless (39), a father-of-one from Bray, Co Wicklow, had been part of an eight-member expedition attempting to scale the world's highest peak.
Led by fellow climber Noel Hanna, Mr Lawless is said to have gone missing after falling from an altitude of 8,300 metres.
It is understood he slipped while in an area known as the Balcony after reaching the summit early yesterday.
His wife Pam and daughter Emma (4) are being kept up to date with any news from the Himalayas.
The other Irish climbers are reported to be safe and currently at 2,400 metres. They are due to descend later today.
The Himalayan Times reported that sherpas accompanying the expedition said the other climbers had descended to Camp Four, but Mr Lawless' status was still unknown.
A spokesperson for Trinity said the university's thoughts were with Mr Lawless and his family during this "extremely distressing time".
"This morning his family, friends and colleagues shared his joy on reaching the peak of Mount Everest," they said.
"We hope that Seamus is found safely as soon as possible and until then we will be offering any support we can to his family."
In February, Mr Lawless told the Herald the climb was part of a trip of a lifetime ahead of his 40th birthday this summer.
He said he was climbing in a bid to raise €25,000 for the Barretstown charity, which provides support for seriously ill children and their families.
Barretstown chief executive Dee Ahearn said everyone at the charity was thinking of Mr Lawless' loved ones as the search continued.
"This is a dreadfully upsetting and uncertain time for Seamus and his family," she said.
"Our thoughts, and indeed the thoughts of the entire Barretstown community, are with Seamus, his family and friends."
Mr Lawless said that when he was a child his father gave him a National Geographic map of the climbing route up the south face of Everest.
It was on his bedroom wall as he grew up, remaining there until he left for Nepal in April.
He said he had been preparing for the challenge alongside fellow climbers from the Ireland on Everest group for four years.
"I turn 40 in July," he said in February. "My friends are joking that climbing Everest is my mid-life crisis."
Climbing beside him was mother-of-four Jenny Copeland (40), who swapped high-speed driving on racetracks for the challenge of scaling some of the world's toughest peaks.
A spokeswoman for the Department of Foreign Affairs said: "We are aware of media reports and stand ready to provide consular assistance if requested."