MANILA: Philippine authorities Friday announced a renewed crackdown against drug syndicates based in China and West Africa following the execution of three convicted Filipino drug mules in China. In a statement, the Bureau of Immigration (BI) said even before the tragic executions it had started denying entry to dubious foreign visitors amid reports that international drug syndicates have been intensifying their activities in the Philippines, which serves as a strategic transshipment hub of illegal drugs. The syndicates usually drop the drugs at many of the country's unguarded coastlines, then retrieve and take them through airports using Filipino drug mules. From January to February this year, the bureau denied entry to 131 foreigners -- 96 Chinese and 35 West Africans -- who have questionable motives for entering the Philippines, said Tonette Bucasas Mangrobang, BI spokeswoman and acting chief of the BI Intelligence Division. Mangrobang said the bureau has imposed tighter guidelines on the entry of Nigerians and nationals from 15 West Africans countries including Senegal, Cote d'Ivoire, Burkina Faso, Benin, Ghana, Gambia and Cape Verde. “They undergo secondary inspection. We really question their purpose for coming to the Philippines...We have a unit that is assigned to monitor arrivals of such nationals. We set aside their arrival cards to monitor their addresses and whereabouts in the country. We monitor their movements,” Mangrobang said. She said a total of 1,276 Nigerians entered the Philippines from March 2010 to March 2011. — Saudi GazetteOf that number, 970 used tourist visas while the rest had student or temporary residence visas issued to foreign nationals who have married Filipinos. In the case of Afro-Filipino couple, the BI spokeswoman said the bureau investigates if the African man and his alleged Filipino wife are really married “or if it is just for purposes of securing the visa.” Meanwhile, the United States indirectly chided China for executing three Filipinos last Wednesday, noting Beijing's dismissal of Manila's repeated appeals for clemency. “It's fairly unusual in Asia when a government makes a very, almost personal, appeal at the very highest levels,” Kurt Campbell, the assistant secretary of state for East Asia, told the US Congress. “I think you know how strongly the Philippines government and President Aquino's own Cabinet felt about this issue. To be turned away in such a manner, I think it was a little bit of a surprise to Filipino friends,” he said. Campbell said on this issue, the United States “supports our Filipino friends.” Campbell made the statement in response to the questions made by Republican Representative Ed Royce, whose district in southern California has many Filipino Americans. Royce also assailed the death penalty imposed by China on the three Filipino drug mules, saying “the radical disparity of the death penalty here when the people organizing it get off scot