'My heart is torn': Wife of Melbourne hero praises her husband

The wife of a Melbourne man who died trying to save children in trouble at Wollongong beach has praised her husband for his bravery.

Shaun Oliver was on a work trip when he rushed into the surf in pursuit of two of four children who got into trouble during a Sunday afternoon swim at Wollongong City Beach.

A surfer reached the pair and got the the older boy closer to shore while an off-duty paramedic helped pull the 10-year-old boy to shore.

Mr Oliver's wife said her "heart is torn". Source: 7 News

Mr Oliver, who helped a 12-year-old make his way to safety, was swept out to sea before being pulled from the water by police and given CPR but later died in hospital.

His wife Carla wrote "My heart is torn into a thousand pieces. I am so proud of you but so so heartbroken to be without you forever... Our kids were counting down the days until you were home."

"Never in my wildest dreams would we see this coming and now we all miss you so much more than I could ever imagine."

Mr Oliver left behind children and his wife. Source: 7 News

All the other children were rescued as an off-duty paramedic and surfer also rushed in to help.

The grateful mother of the four children, Islam Hammad, broke down as she recalled to 7 News the moment Mr Oliver disappeared underneath the waves.

“They had been very close to us, not far and suddenly the waves became very crazy and they started to get to the back of the beach," she said, choking back tears.

“This man went in and saved one of the children... then the man suddenly disappeared.”

Islam Hammad said Shaun Oliver was a hero for saving her children. Source: 7 News

"I feel trouble for myself that I couldn't save him... he didn't think about anything, he just went straight in the water.

"He is a hero. I'm sure he is very happy in the place that he is now."

Mr Oliver leaves behind his "childhood sweetheart" and three young children.

A man has died trying to save children from drowning at a NSW beach. Photo: 7 News

Detective Inspector Brad Ainsworth said a man has died because a simple message was not followed.

“No flags, no swim. It’s a simple message, but it just doesn’t get through," he said.

The 32-year-old was swept out to sea while trying to save two children from drowning. Photo: 7 News

“A (man) has died as a result of his heroic efforts to rescue four children from the surf.

“It really puts individuals who come to the aid of people in danger."