Hong Kong’s justice minister hurt her arm when she fell while on an official trip in London on Thursday, in what was the first physical confrontation between a cabinet official and Hong Kong protesters.

Teresa Cheng Yeuk-wah, who is in London to promote Hong Kong as a centre of dispute resolution, appeared calm but shocked while surrounded for several minutes by at least 30 protesters angry about the administration’s handling of the anti-government protests.

She later made a report to the London police and asked them “take the case seriously and put the culprits to justice”, her office said in a statement.

“The Secretary for Justice castigates the violent mob in London today causing her serious bodily harm on her way to an event venue,” it said. “The secretary denounces all forms of violence and radicalism depriving others’ legitimate rights in the pretext of pursuing their political ideals, which would never be in the interest of Hong Kong and any civilised society.”

Videos circulated on Twitter did not reveal whether someone pushed Cheng onto the ground or she fell.

The Chartered Institute of Arbitrators, which organised Cheng’s talk, said in a statement: “Secretary Teresa Cheng, whilst entering the building, was assaulted by a crowd. As a result she sustained an injury to her arm.”

“CIArb is committed to peacefully resolving conflict and deplores the use of violence, particularly to a guest to the United Kingdom,” it added.

“Shame on you” and “five demands, not one less” were some of the slogans shouted at her during the several-minute-long confrontation in London – something Cheng was not known to be subject to in Hong Kong during the last few months of citywide protests.

Others shouted “murderer” at her. At least one protester has died during the protests, which began in June when the government tried to introduce an extradition law that would have allowed the transfer of fugitives between Hong Kong and jurisdictions it doesn’t currently have an agreement with, including mainland China.

The law has since been withdrawn.

Cheng, the top legal adviser for Chief Executive Carrie Lam Cheng Yuet-ngor, is widely seen as one of the key figures in drafting the now-shelved legislation.

The justice secretary had the lowest popularity rating – at minus 68 per cent – among all Lam’s cabinet members, according to a poll by the Hong Kong Public Opinion Research Institute that was released this week.