Marine police arrested seven mainland women trying to cross the border illegally by sea at Deep Bay yesterday. Officers spotted a five-metre-long speedboat, which had no navigation lights, near the Hong Kong-Shenzhen Western Corridor at about 2.30am. They pursued it and when it ran aground at Ngau Hom Sha, Lau Fau Shan, eight passengers ran ashore. Police arrested the seven women, but a man, whom police suspect was the "snakehead" or organiser, fled on foot. Three of the women, aged from 52 to 59, had two-way permits which had expired two years ago. Police believe they had worked illegally in Hong Kong before making an attempt to return home. The other four passengers had paid 3,000 yuan (HK$3,700) each to sneak into Hong Kong from Shekou and had stayed on board the speedboat as they had not reached their drop-off point. The officer said marine police arrest between 30 and 50 mainlanders as illegal immigrants or overstayers every year as they attempt to sneak back to Shenzhen and Shekou by boat after working illegally in Hong Kong. "But some are intercepted after being found on remote islands, such as Ping Chau, where they wait to be picked up by their snakeheads," a veteran police officer said. "One or two have even been picked up while trying to swim the three kilometres across the border in Deep Bay." He said the northbound journey, which usually took less than 30 minutes, cost between HK$500 and HK$2,000. Most of those apprehended wished to return home after having saved sufficient money from illegal employment as cleaners, dish-washers and construction and renovation workers. "Some arrived with travel documents and some were illegal immigrants," the officer said. "They do not surrender to police because they fear they would not be allowed to apply for travel documents and would be fined after being repatriated." The officer said marine police usually intercepted more people trying to sneak back home before Lunar New Year as they wanted to return for family reunions. During a search on the shore, after yesterday's capture, police arrested a Vietnamese woman, 32, at a temple nearby. She said she was waiting to be picked up to return to Vietnam via the mainland.