A father has died while trying to rescue his daughter from the river near Pantperthog, in Machynlleth, Powys.
The child was rescued from the water but the man then got into difficulties.
Dyfed-Powys Police helped by ambulance and fire crews tried to rescue the man but his body was later recovered from the river.
Police have launched an investigation and are notifying next-of-kin, believed to be from the north west of England.
The incident happened just south of the road bridge which crosses the river Dulas, close to the Centre for Alternative Technology.
The man was staying at Llwyngwern Farm Camping and Caravan site with his two daughters.
Camp site owner Ralph Beaumont told BBC Wales it was an "awful tragedy"
Mr Beaumont said the man drowned after he went into the river to help his daughter who had got into difficulty after she had herself gone in after the family's pet dog.
He said the man was sitting outside his tent on the bank when the tragedy happened.
The man "rushed down and dived in after her" and "obviously got into difficulty in the water", Mr Beaumont added.
Other people staying on the site made every effort to resuscitate the man, he said.
Mr Beaumont said the girl and the dog were "both fine" and that the family had come to the camp leaving their mother at home for a quiet weekend on her own.
Eyewitnesses, who did not want to be named, said the man had lost consiousness when he was eventually dragged ashore.