A 15-year-old Birmingham boy had to be freed after his leg became stuck in wet sand with the tide coming in.
The teenager was on holiday with his family when he sank up to his knees at the water's edge on Charmouth Beach, Dorset.
Portland Coastguard said his stepfather called 999 just before 9pm on Monday and the crew of Lyme Regis RNLI lifeboat and Coastguard rescue officers went to release him.
The boy, who has Asperger syndrome, was checked over by a medical adviser and was cold and shaken but unhurt.
RNLI lifeboat crew medic James Rice, doctor Forbes Watson and their colleagues, John Cable, Andrew Rice and Tim Edwards, went to help.
An RNLI spokesman said: "The boy had sunk up to his knees with the tide coming in when the lifeboat was launched at 9pm."
A Coastguard spokesman said the family were staying at a camp site and added: "They were walking along the tide line and he got his foot and half leg stuck in the sand and couldn't get it out."
He added: "There are parts where it can be a bit more mud than sand. There has been a couple of land slumps rather than land slides down that way so there are parts that can be a bit softer."