Emergency crews have used a helicopter to pull five people from the water after their boat capsized in the Nepean River in Sydney.
The boat overturned just after 3.15pm on Sunday with a multi-agency rescue operation managing to winch three adults and two children to safety in Sydney's west.
"This was an extremely difficult scene, and horrendous to watch, with five people struggling in the water as responders tried to rescue them all," NSW Ambulance Inspector Peter Van Praag said.
"Three of the patients had aspirated water and will need ongoing care in the hours ahead."
Police said a man was taken to Westmead Hospital in a critical but stable condition and the two other adults - a 34-year-old man and 27-year-old woman - were taken to Nepean Hospital in a stable condition.
Two children - a five-year-old boy and a six-year-old girl - were taken to the Children's Hospital at Westmead in a stable condition, police said.
Insp Van Praag said the children were wearing life jackets which helped prevent the accident turning deadly.
A 33-year-old woman died last week also in the same area on the western Sydney river when a boat with four other people on board capsized.
She was pulled from the water unconscious and treated by paramedics but died a short time later.
"I really can't warn people strongly enough - to take care and be safe out on the water," Insp Van Praag said.
