The desperate act that saved the lives of two people after catamaran capsized

An emergency beacon was activated from a capsized catamaran before three people were found dead and two others were rescued off the coast of NSW.

Just after 10am on Thursday a signal from an Emergency Position Indicating Radio Beacon (EPIRB) was sent to the joint rescue coordination centre in Canberra, alerting them to trouble in the water about 12 kilometres off Stockton Beach in Newcastle.

Rescue teams who then attended the scene found a capsized 11.7-metre catamaran and three people, aged in their 60s and 70s, dead in the water.

Two survivors had been clinging to the catamaran when they were found by rescuers. Source: Nine News

Two who were still alive were clutching onto the overturned vessel, which had left Shoal Bay earlier on Thursday morning and was heading south toward Ettalong Beach on the Central Coast.

NSW Police Acting Superintendent Grant Healey told reporters all five people were wearing life jackets at the time they were found.

Superintendent Healey said that decision likely went a long way to saving the lives of the two survivors.

Two rescued suffering from hypothermia

The two survivors winched out of the water by the Westpac Rescue Helicopter Service were a 16-year-old girl and 40-year-old man.

Superintendent Healey said it wasn’t clear how long they had been in the water but they were suffering from hypothermia.

The catamaran will not be able to be retrieved until conditions calm. Source: Nine News

“But it is the cold season and it doesn't take long to get hypothermic,” he told reporters.

The relationship between those rescued and the deceased are not yet known.

The pair are being treated for hypothermia in John Hunter Hospital.

‘It was fairly messy out there’

Rescuers battled rough conditions as they attempted to retrieve the two survivors from the water.

Ambulance NSW Inspector Luke Wiseman said the rescue mission was complicated by high seas, strong winds and debris in the water.

It is unclear what caused the boat to capsize, but Superintendent Healey said the conditions were difficult.

"We had 25 to 30 knot westerly winds with the sea at one to two metres coming the other way. So it was fairly messy out there," he said.

NSW Police Marine Area Command Detective Acting Superintendent Grant Healey says the conditions were 'fairly messy'. Source: AAP

Authorities have not yet been able to recover the overturned catamaran, which is drifting out to sea.

"As soon as there is favourable sea conditions there will be an attempt to salvage the vessel," Superintendent Healy said.

"But whilst the weather is like it is, all we can do is let the boating community know where it is."

A strong wind warning is in place along the NSW coast, from the Hunter down to Eden.

Roads and Maritime Services are urging fishers and boaties to be extra cautious, with choppy conditions expected on exposed bays as well as dangerously rough conditions offshore.

- with AAP

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