Hong Kong police arrested two more Chinese University students on Tuesday over an assault on campus security guards, bringing the number of suspects detained in the case to seven. The two men, aged 22 and 24, were apprehended in different dormitories of the university in Sha Tin at about 7.30am, according to a police source. Officers arrested the pair on suspicion of unlawful assembly, and assault with intent to stop guards performing identity checks at the campus entrance. University head condemns ‘shocking’ attack on security at Hong Kong campus As of 12.30pm, the two suspects were being held for questioning and neither had been charged. On January 11, a masked group dressed in black charged the security barrier at the guard post near University MTR station in Sha Tin. The gang knocked down railings and threw an unknown white powder at guards before fleeing in different directions. At the time, staff caught one of the suspects, while the others got away. The 20-year-old man, a university student, was then arrested on suspicion of disorderly behaviour in a public place and assault. The incident left one of the guards feeling unwell after coming into contact with the powder. He was sent to Prince of Wales Hospital in Sha Tin for treatment. On January 25 and 26, police arrested another four students of the university in connection with the case. Police said in January that the group was believed to have launched the attack to challenge a university policy requiring security guards to perform identity checks at campus entrances. Detectives from the New Territories South regional crime unit are handling the case.