Eight people were arrested yesterday for the kidnap and murder of an 11-year-old girl whose body was found floating off a beach at Ap Lei Chau. One of those arrested was a relative of the victim's family, according to a police source. The source said the man lured the girl from her Tai Po home on Friday afternoon on the pretext of taking her to Ocean Park. The girl, surnamed Tse, was the second kidnap victim to be killed in less than three months. On July 14, the body of 11-year-old Chan Chi-sin was found under a flyover near Kai Yip Estate. Six people, including a 12-year-old girl, were arrested in connection with his death. Police said the girl's body was found floating off Tung Kok Beach near Ap Lei Pai shortly before 2pm yesterday. She had marks on her neck and appeared to have been strangled. Detectives were able to identify the girl with the help of her family members two hours later. By 7pm detectives raided two flats in Sham Shui Po and Tuen Mun and arrested six men and two women aged 26 to 58. Police said the girl's family received a call at about 9pm on Friday demanding $500,000 for her safe return. Her father is a truck driver. The family contacted police, and detectives from the New Territories North Regional Crime Unit were assigned to the case. According to the police source, they traced one of the calls to the relative, surnamed Lee. A police spokesman said no ransom had been paid. Detectives believe the girl was killed in one of the two flats before her body was dumped into the sea.