A Hong Kong migrant has been arrested in Vancouver on allegations of operating a loanshark and extortion ring. Tam Kwok-chung, 40, has been charged with extortion and possession of weapons and drugs. His wife, Yip Chui-lin, and two mainlanders, Zheng Huoquin and Chang Yihua, are being held on similar charges. Police said Tam belonged to the Big Circle gang and was highly placed in organised crime in the city. Vancouver police spokesman Anne Drennan said they approached victims at casinos, lent money and then charged 10 per cent interest a week. Police said the gang was broken after an elderly Chinese woman reported that she had borrowed C$15,000 (HK$75,000). The gang demanded a weekly interest repayment of C$1,500. Unable to pay, she said the gang beat her up, forced her to sign a document and then took away a Mercedes car and all her household furniture.