New South Wales Police say three young people are "safe and well" after they were swept away by "fast moving" water while swimming in the Hunter River.
Multiple emergency crews rushed to a private property off Annandale Row at Denman, in the Upper Hunter region, around midday.
A 14-year-old girl was swimming with two boys when all three were swept away by "swift" water.
NSW SES commander for Upper Hunter Andrew Aboozaid said SES crews from Muswellbrook and Singleton responded.
"The first child ... had been trapped against tree root bulb and was struggling to hold their head above water," he said.
NSW Ambulance Inspector Mark Gardiner said the 14-year-old girl had been swept downstream and "her foot became stuck".
"NSW Ambulance paramedics, alongside RFS and SES swift-water crews, worked to release the girl's foot and get her safely to shore," Inspector Gardiner said.
"She was assessed by paramedics and treated for some hypothermia.
"The children remained calm and were in good spirits throughout the operation.
"We're thankful that we could reunite this family and that no-one was seriously injured."
"Thankfully we weren't in full flood conditions but it's just a timely reminder coming into the current holiday season, to take appropriate precautions when we've got children around the water," Mr Aboozaid said.