Emergency services have launched a river search looking for a man who disappeared after a kayak capsized as Storm Katie hit Britain.
Crews out in rubber boats and a police helicopter are scouring the River Wey in Guildford, Surrey, looking for the man, who disappeared in the water.
Onlookers said he had gone to help his son, who is believed to be around 12 years old, when he was overcome by the strong current.
They said the kayak "was being dragged around like a bottle very fast" and while the boy made it to safety, the man vanished in the water.
Kayla White wrote on Facebook: "Police divers are going in to search, and fire rescue told me that it was his son (who) was kayaking and got into trouble, and he went in (and) got his son to safety and didn't get out.
"So he put his life at risk to save his kid, and to be honest I would do the same to all my kids."
Niamh Saul wrote: "No he hasn't been found...but the small boy was saved. God bless the father saving his son and he got washed away. Heartbreaking, thinking of his family and friends."
Christopher Jackson wrote on a community Facebook page: "(I) heard (a) dad telling (his) son how to paddle in passing ... we could see the canoe was being dragged around like a bottle very fast."
Officers were called to the river Millmead, near to the Guildford Borough Council offices, at around 1.10pm on Monday.
Search-and-rescue crews combed the river all afternoon looking for the man, who has not been named.
The disappearance came after Storm Katie bought rain and winds of up to 106mph to southern England.
It toppled trees, bent industrial cranes, and ripped off roofs as it swept over the country.
Around 100,000 homes were hit by power cuts, while planes were diverted, trains delayed and roads left treacherous by the bad weather.
The Environment Agency issued a flood warning for the River Wey in the Godalming area which, it warned, "has been rising steadily throughout the day in response to recent rainfall".
The Wey Kayak Club warned on Twitter on Monday that the river had "dangerous conditions".
Commenting on the search for the missing kayaker who, according to some reports also had a dog with him, Surrey Police Chief Inspector Dave Mason said: "We have a large number of officers out looking for this man alongside a number of fire crews.
"The man was spotted in the water by several members of the public and was clearly in difficulty due to the extremely strong current.
"We are doing everything we can to try and find him. We are urging members of the public that if they do see him, not to try and go in after him but to call 999 straight away."