Hong Kong police have warned of the threat of further violence during anti-government protests after the discovery of a petrol bomb that had been modified to make it more lethal, during raids where a variety of weapons were seized. The enhanced bomb was found during the search of a flat in Tin Shui Wai on Thursday, along with six other uncompleted petrol bombs, 30 smoke bombs, potassium nitrate, an explosive material used for making gunpowder, and HK$500,000 (US$63,800) in cash. A woman, along with her son and daughter, all aged between 23 and 47, were arrested at Shui Moon House for illegal possession of explosives. A further eight people were arrested in Sha Tin, after police raided an industrial estate and found another cache of weapons, including baseball bats, sharpened sticks, and bows and arrows. “Some substance has been added to the bombs to make them more lethal,” said Li Kwai-wah, senior superintendent of Organised Crime and Triad Bureau. “The force is worried about the violent protests in recent days, which saw smoke bombs and iron marbles being used, an escalation from previous protests where water bottles and bricks were being thrown at officers.” Li also attacked the “hateful” comments directed at the force online, adding, “there is a correlation between the increasing violence and the online speech inciting that violence”. He also confirmed the seizure of an imitation firearm during the July 27 protest in Yuen Long. “If someone takes out or uses the imitation firearm at a very chaotic and complicated protest, it can lead to very grave consequences as nobody would know if that is real or fake,” Li said. In a raid on a flat in Haribest Industrial Building on Au Pui Wan street in Sha Tin on Thursday night, police arrested seven men and one woman, including Andy Chan Ho-tin, the founder of the outlawed Hong Kong National Party. The group were arrested on suspicion of possession of offensive weapons, possession of instruments fit for unlawful purpose, and possession of explosives without a licence – which could attract a maximum penalty of 14 years in jail. Officers escorted Chan, who had his hands chained to his waist, to his home in Shui Chuen O Estate in Sha Tin for a search on Friday afternoon. Unprecedented violence during extradition bill clashes in Hong Kong’s Sha Tin Seized items from the industrial building included a petrol bomb, 10 baseball bats, 20 sharpened walking sticks, 15 sets of walkie-talkie, two bows, six arrows, metal balls and several cartons of protective gear – such as helmets, gas masks and arm guards. Some bottles believed to be used to make petrol bombs were also seized, along with oil containing suspected cannabis content, black and white T-shirts, and a cane. Li said they would investigate if the weapons, which were similar to items found during the recent protests, were related to the demonstrations. The arrests and seizures were made after officers spotted four of the suspects pushing a trolley loaded with a carton box and several red, white and blue nylon bags. Officers raided a flat in the industrial building after finding a key from one of the suspects. The arrest of the eight people prompted hundreds of their supporters to gather outside Sha Tin and Ma On Shan police stations, where Li condemned them for damaging security cameras and communication devices and spray-painting the walls of the premises. Police chief urges unity among officers Meanwhile, police arrested seven more men, aged between 18 and 55, for unlawful assembly in relation to the mob attack at Yuen Long MTR station on July 21. Police said some have triad backgrounds, bringing the total number of arrests so far to 19. The first 12 men, nine with suspected triad background, have been bailed out. Chan Tin-chu, senior superintendent of the New Territories North regional headquarters, said more offences could be involved if further information was found during the investigation. But he did not explain why police could take action more swiftly against extradition bill protesters than against Yuen Long attackers. Separately, three Hong Kong residents have been arrested on suspicion of inciting people to commit crimes and trying to get a loan using personal data of a police officer leaked online. The three men, aged between 26 and 39, including an interior designer and a decoration worker, were picked up in a series of raids across the city since Tuesday. They had been released on bail and none of them were charged. Chaos, tear gas and anger as protesters descend on Yuen Long One of them was arrested for inciting others to attack police with weapons and the other was accused of calling on people on the Internet to besiege an officer’s flat. The third man was arrested on suspicion of fraud, after he allegedly tried to use a policeman’s personal data to apply for a loan.