The 10-year-old son of Doreen Haggar, 46, attended one of Hamilton's boys' clubs in Linlithgow, central Scotland, in 1988. Mrs Haggar, who now lives in Aberdeen, said that her son had gone to Loch Lomond for a two-week summer camp with the club.
After less than a week her son had returned home. A police officer had telephoned her house, saying her son would be returning. "He was tired, weepy and agitated," she said.
Hamilton had thrown him out of a boat into the loch. At the camp Hamilton had taken away the boys' clothes, telling them to wear only swimming trunks.
Mrs Haggar went to the camp to pick up her son. She stayed to help but later told him she was leaving and would inform the police and authorities that the camp included none of the facilities parents had been promised.
Mrs Haggar told the inquiry before Lord Cullen, which is investigating the mass murder of 16 Dunblane primary school children and their teacher, who were shot dead by Hamilton on 13 March, that Hamilton had been mistreating and hitting the boys in his care at the camp.
In a police interview with her son, it was revealed that Hamilton had asked boys to rub sun tan oil over him.
After the complaint Hamilton had driven to her home in Linlithgow. "He leant forward to start the engine. The next thing I heard was a click, like metal hitting glass."
She looked again and saw a gun-barrel. "I said, 'Put that effing thing away before I ram it down your throat. He never said a word. Off he went," she said.Mrs Haggar later reported the incident to police.
The inquiry was also told that council officials had suspicions about a boys' club run by Hamilton, but lacked hard evidence to justify stopping him from hiring premises.
Douglas Jeffrey, a youth and children's work development officer in Edinburgh, was sent to see Hamilton in May 1988. He visited him at a club Hamilton ran at Linlithgow Academy, after a complaint from a parent whose son signed up for, but did not attend one of his summer camps, and who was being pressed for money by Hamilton.
Mr Jeffrey told the Stirling inquiry that he was "uneasy" about Hamilton. Based on his investigation, a report recommended Hamilton's club be deregistered, but he said yesterday: "We did not have enough hard evidence ... to withdraw the let."
Earlier, the family of Gwen Mayor, the murdered teacher, spoke for the first time of both their pride and grief. Mrs Mayor's daughters Esther, 21, and Debbie, 19, collected their mother's posthumous award of Scotswoman of the Year at a lunch in Glasgow organised by a Glasgow newspaper.
They said they were "overwhelmed" but filled with sadness that their mother could not attend an occasion held to honour her. The inquiry continues.Reuse content