Hong Kong police seized high-powered explosives during a raid on a suspected bomb-making factory on Friday night, on the eve of planned protests across the region over the weekend.A 27-year-old man was also arrested by the police from the "homemade laboratory" in Tsue Wan, according to CNN.Two kilograms (4.4 pounds) of high explosives, 10 petrol bombs, corrosive liquids, weapons and metal poles have been seized by the police in Friday night's raid."It's the largest such seizure we have ever come across in Hong Kong," Alick Mcwhirter, the superintendent of the Explosive Ordinance Disposal (EOD) Bureau, said.Flyers linked to the anti-extradition bill protests were also found on-site during the raids, CNN added.Both pro-government and anti-extradition bill protests are scheduled for Saturday and Sunday across Hong Kong.While the police were still testing the seized materials, they believe that triacetone triperoxide (TATP) was found at the site of the raid.Law enforcement officials have .