During this time, he met Oscar Guerrero, a freelance journalist from Colombia. Guerrero persuaded Vanunu to sell his story, claiming that his story and photographs were worth up to $1 million. After failing to interest "Newsweek", Guerrero approached the British "Sunday Times", and within a few days, Vanunu was interviewed by "Sunday Times" journalist Peter Hounam. According to American journalist Louis Toscano, Guerrero approached the Israeli consulate in August 1986, offering help in tracking down an Israeli "traitor". Guerrero was hoping to be paid. He met with an Israeli intelligence officer named Avi Kliman and told him Vanunu's story. Kliman was initially dismissive but took down Vanunu's name and passport number, which was checked. They met a second time, during which Guerrero handed over four crudely copied photographs. On September 7, 1986, two men who identified themselves as officers from Shin Bet approached Vanunu's older brother Albert in his carpentry shop in Beersheba and questioned him about his brother. They told him that he was in Australia, that he was talking to a British newspaper about his work at the nuclear research center, urged him to dissuade his brother, and then made him sign a non-disclosure agreement barring him from talking about the meeting. On September 10, Vanunu and Hounam flew to London from Australia. There, in violation of his non-disclosure agreement, Vanunu revealed to the "Sunday Times" his knowledge of the Israeli nuclear programme, including the photographs he had secretly taken at the Dimona site.