HONG KONG – The city’s police seized a homemade bomb and some poisonous and inflammable chemicals at an abandoned school in Kowloon Bay Saturday, the 11th time for police to find explosives in Hong Kong since beginning of social unrest last year. 

Li Kwai-wah, senior superintendent of the Organized Crime and Triad Bureau of the Hong Kong Police Force, said the homemade bomb was found at a men's room of the school, along with remote control devices, a pressure cooker and four kgs of ammonium nitrate explosives after the police received a report at noon. 

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Li said finding the pressure cooker was an alarming signal as the seemingly harmless kitchenware is frequently used in terrorist attacks across the globe. 

It is reported that an explosive device made of a pressure cooker containing bombs, nails and other hard objects will cause more casualties after being detonated remotely by a mobile phone or an alarm clock. 

About 10 kgs of chemicals including quicksilver were also seized during the operation. Those were suspected to be stolen from the laboratory of the Hong Kong Polytechnic University during the two-week occupation by the radicals in November. 

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Police also said Saturday evening that a 15-year-old male and a 46-year-old female were arrested for throwing petrol bombs on the street and possessing gasoline with intent to damage property.