POLICE are hailing the success of a clampdown on mainland prostitutes in Macau which has seen almost 400 women and a dozen pimps thrown out over the past nine months. In the week that three women died after marine police intercepted a boatload of vice girls heading across the narrow stretch of water between the mainland and Macau, unofficial figures reveal a sharp increase in arrests and expulsions. A government source said that on top of cross-border vigilance, raids in recent months on nightclubs and red light areas had led to an increase in arrests including that of club owners. At the latest count, the source said, 371 women - mostly from neighbouring mainland provinces - had been expelled for immigration-related offences, and all were suspected of involvement in the sex trade. Eleven pimps have also been fined 5,000 patacas before being kicked out and 24 club bosses charged with hiring illegal workers. The crackdown follows the passing of new laws in August last year which give police greater powers to arrest people involved in the organisation of prostitution. While prostitution is not illegal, soliciting is. Official statistics also show that in 1996 just under 70 per cent of all illegal immigrants who entered Macau from China were women. Most were aged 20 to 29 and 93 per cent arrived in the enclave by boat from nearby Zhuhai. The next biggest group were the 5.6 per cent so desperate they swam across the short stretch of water separating the two territories. Most are under no illusions about what awaits them when they arrive in Macau and many who arrive on a seven-day visitor permit have little or no intention of leaving when it expires, the source said. A Catholic nun from the Good Shepherd Sisters shelter who has worked in the enclave for several years said: 'It's true most of these women come here because they want to, but their situation is so bad in China you can hardly call it a free choice. 'Many of them live in fear - fear of customers and fear of their pimps, they're working in a hostile environment.'