Pro-democracy activists Finn Lau and Christopher Mung were speaking at the briefing in a private room at the Commons when a man believed to be sent by China's Communist Party tried to get in
The investigation comes after the Daily Mail revealed that a man claiming to be a tourist tried to gatecrash a private event in the Palace of Westminster.
EXCLUSIVE: A man claiming to be a tourist tried to enter the invitation-only talk in a room within the Houses of Parliament. The meeting was addressed by Finn Lau and Christopher Mung.