Tributes have poured in to honour the three men who died in a boating accident on the NSW North Coast yesterday.

Tragedy struck after a member of the public called emergency services about 6.15pm to report a yacht having difficulties off the South Ballina break wall.

Police said Marine Rescue NSW crew responded, but their rescue boat capsized while crossing the Ballina bar in “heavy conditions”.

Bill Ewen and Frank Petsch. (Supplied)
Three people have been killed in a tragic attempted marine rescue off the Ballina coast. (9News)

Three men were killed, including the sole sailor onboard the yacht, Matthew Clayton, and Marine Rescue volunteers Bill Ewen and Frank Petsch, who set out in treacherous conditions in response to the yacht in distress.

Four other crew members were on the Ballina 30, with three being hospitalised with broken bones and other non-life-threatening injuries.

Among the survivors was Ballina Shire Citizen of the Year Geoff Hutchinson, who suffered serious injuries in the rescue attempt.

The rescue vessel that capsized. (9News)

Marine Area Command Superintendent Joe McNulty said the rescuers had faced “severe conditions” including 2.5-metre swell as they travelled downriver towards the ocean.

At the Ballina bar, a wave of similar height proved too difficult to navigate, and the boat foundered and capsized.

Of the six men on board, McNulty said some were trapped beneath the boat’s hull and some were thrown from the vessel entirely.

“These men are heroes. They volunteer their lives to save others,” McNulty said.

Emergency personnel scour the beach. (9News)

The rescue boat and other fragments washed up on the shore today as tributes flowed in at the Marine Rescue tower to honour the men.

“They’re a big part of the community,” a local told 9News.

“This bar and this waterway cops a lot of boats coming through, it’s really sad.”

Tributes have poured in to honour the three men who died in the tragedy. (Nine)

McNulty said the accident would be investigated.

Officers at the time of the incident did not know how many people had been aboard the yacht, and launched a coordinated search with the help of paramedics, the SES, the Westpac helicopter, and the AMSA Challenger jet.

A Westpac Rescue Helicopter on the ground in Ballina. (Nine / Supplied)

McNulty said police divers would likely enter the water on Thursday when the seas were safe enough to do so, in order to gather evidence from the yacht’s wreckage.

McNulty said the yacht, which he believed was NSW-registered, had crashed into the break wall and broken apart.