--FILE--View of casinos, residential houses and apartment buildings in Macau, China, 31 May 2013. Macau will reduce the maximum number of days that Chinese passport holders with transit visas can stay in the city to five from seven, in an attempt to prevent them from abusing the law. Casino shares dropped. Transit visitors from China who do not depart for another destination within the five days will be in violation of the new rules, effective July 1, and will be penalized upon their next visit, the citys Public Security Police Force said in a statement yesterday. Repeat violations will result in denial of entry, according to the statement. Chinese tourists have been driving the revenue of casino companies in the worlds largest gambling hub, including Sands China Ltd. and Galaxy Entertainment Group Ltd. They are competing for gamblers by adding malls, theaters and restaurants at their resorts. An improved rail connection and an increase in hotel rooms are helping draw more vacationing Chinese to Macau and the countrys only legal casinos.