The body of a four-year-old boy who slipped from a jetty is believed to have been washed out to sea after specialist sonar equipment failed to find him, experts say.
Dylan Cecil was on holiday with his family when he stumbled into the muddy water at Burnham-on-Sea, Somerset, at 6pm on Sunday.
His mother, Rachel McCollum, said he fell into a "whirlpool" and she knew immediately that she would not see him again despite her desperate efforts to save him.
Volunteers from the UK underwater rescue organisation SARbot used specialist sonar equipment to scour the water for Dylan's body. But after spending hours on the water his body could not be found.
The organisation was using sonar equipment which is more sensitive than that used by police and had earlier said that if the youngster's body was still in the area, they would find it.
Duncan Winsbury, chief executive of SARbot, confirmed the search had been brought to an end.
"We've just completed the search and have searched the whole bay and we've not found anything," he said.
"We believe that the currents may have taken him right out to sea now, he's certainly not in the bay."
Dylan, from Kettering, Northamptonshire, was visiting his grandparents with his mother, father Darren Cecil and two younger sisters, aged one and three.
He had wanted to get a closer look at the sea when he slipped off the side of the jetty and disappeared beneath the water. His parents desperately tried to rescue him, but were unable to reach their son and had to be pulled from the water by passers-by.