A surge in mobile phone theft has given the police chief a headache, despite Hong Kong now being safer than a decade ago. Police Commissioner Dick Lee Ming-kwai said the number of crimes in the first half of the year dropped by 7.5 per cent on the same period last year, when the annual crime figure rose to an eight-year high. But while the city can take comfort from a drop in serious offences, police face a a surge in petty crimes, including mobile phone theft. 'The mobile phone problem is our biggest headache ... you can make a few hundred dollars in the second-hand market,' Mr Lee said. 'There has been a sharp rise in the number of mobile phones stolen over the past one to two years.' He said that while police could step up patrols in pickpocketing black spots, there was a limit to enforcement action, as many of the thefts happened in areas not patrolled, such as in restaurants or on public transport. 'Say you leave your mobile on a table in a fast-food shop while reading the newspaper or go and get a packet of sugar, the handset could be stolen,' Mr Lee said. More than 6,000 mobile phones were stolen last year. Police are now targeting the channels where thieves sell their handsets. They estimate 700 mobile phones are traded in Apliu Street, Shamshuipo, every day, many believed to have been stolen. Officers arrested 15 people and seized more than 800 suspected stolen phones in the street last Friday. Mr Lee said the mainland solo travel scheme had indirectly led to more petty crime, with tourists often falling victim. 'We can see that crimes brought about by the solo visitor scheme, like pickpocketing, are on the rise with more tourists carrying cash [to go] shopping here,' he said. There were 797 pickpocketing cases in the first five months of the year, nearly five a day compared with only two a decade ago. But Mr Lee said there were 1,300 offences per 100,000 head of population last year. Ten years ago the rate was 1,400. Strengthening intelligence exchange and law enforcement had also resulted in a significant drop in the number of serious crimes. An average of 17 robberies of all kinds took place each day in 1994, compared with only seven cases today. Mr Lee attributed the drop to Hong Kong losing its attractiveness as a target for gangsters, as mainland cities now had as many banks and jewellery shops as the city.