A Hong Kong man has been arrested in Shenzhen after a brutal chop attack in which his wife died and his step-daughter and another man were critically injured. Construction worker Tsang Yam, 40, was last night being detained at the Buji Public Security Bureau. His wife, Zhu Yuetfei, 37, was found naked with multiple chop wounds in their first-floor flat in Bo Lei Road, San Sam Tsuen. She was certified dead on arrival at a government hospital. The injured man, who worked for the couple performing household chores, escaped by jumping out of a window wearing only his underwear. Both he and Zhu's teenage daughter were in a critical condition suffering chop wounds. Their names were not released. Tsang, who is unemployed, married mainlander Zhu about 10 years ago and lived part of the time in the Buji flat with his wife and her three children from a previous marriage. Zhu had obtained a Hong Kong identity card and became an SAR citizen but continued to live in Buji. A Shenzhen Public Security Bureau officer said Tsang returned to the flat at about 2am and was involved in a dispute with Zhu, during which he allegedly attacked her and her daughter with a knife. He also allegedly attacked the man, whose cries for help alerted neighbours, who called the Public Security Bureau officers. The officer said the exact cause of the family tragedy was still being investigated.