Searches will resume today for the man’s son who is still missing after the three got into difficulty on rocks near the landmark Beacon at the mouth of Baltimore harbour at around 6.30pm.

The man’s teenage daughter, who saw the tragedy unfold and raised the alarm, was being comforted by family last night.

One friend spoke last night of a deep sense of shock in the community.

“It’s just such an appalling tragedy,” said one man who knows the family well.

“The weather wasn’t bad at the time. There was a bit of a surge but sometimes the ocean can be just so unpredictable.”

It is believed the group of four was walking on rocks in an inlet near the Beacon structure — in an area known locally as Eastern Hole — when tragedy struck.

The area on the seaward side of Baltimore Harbour is visited regularly by walkers and fishermen.

A man was swept to his death in the area about 30 years ago but locals said there was nothing to indicate that a similar tragedy would strike last night.

Rescuers believe that two in the group may have been swept into the water initially and that a third may have entered the water in a desperate bid to save them.

However, the man, named locally as Barry Ryan, in his 50s and believed to be from Dublin but living in the area with his partner for some time; his son, Barry Davis Ryan; and his son’s girlfriend, Niamh O’Connor, who is in her 20s and from Cork City, got into difficulty within seconds.

The teenage daughter, who was still on the rocks, raised the alarm immediately.

A full-scale search and rescue operation was launched involving RNLI lifeboats and local coast guard units. Baltimore inshore and all-weather lifeboats were on the scene within 12 minutes.

They recovered the father and his son’s girlfriend from the water unconscious and in critical condition a short time later.

Baltimore RNLI’s Kieran Cotter said the bodies were found about 30 yards off shore. “We’re still not 100% sure exactly what happened but it’s an awful tragedy,” he said.

“There was a very good medical response. Unfortunately, there was nothing they could do.”

Two coastguard helicopters were tasked — one to airlift the father and his son’s girlfriend to Cork University Hospital and the other to start searching for the missing man. However, despite medical assistance in the pier in Baltimore, the two casualties were pronounced dead at the scene a short time later.

Their bodies were later transferred to Cork University Hospital, where autopsies are expected to take place later today.

Meanwhile, lifeboats, coastguard boats, and divers began searching for the man’s missing son.

The search was stood down as darkness fell around 10pm last night and is due to resume at first light today.

UPDATE: Search due to resume at first light for a man in his 20s still missing at sea after a double drowning tragedy in #Baltimore #Cork — Eoin English (@EoinBearla) June 30, 2015

Meanwhile, three adults and two children were rescued from Annestown beach in Co Waterford at around 6.30pm last night after they became trapped on a sandbank by the incoming tide.