United Kingdom Prime Minister Theresa May on Friday suspended senior politician Mark Field after a video showed him manhandling a protestor at an event in London, BBC reported. The assault took place on Thursday when Field, who is Britain’s minister of state for Asia and the Pacific, was at a black-tie event.

Field attacked a demonstrator from Greenpeace United Kingdom when she had interrupted a speech by Chancellor Philip Hammond. Field said he had reacted instinctively. “There was no security present and I was for a split-second genuinely worried she might have been armed,” ITV quoted Field as saying. “As a result, I grasped the intruder firmly in order to remove her from the room as swiftly as possible.”

Field said he has referred himself to the Cabinet for an inquiry into the incident, and apologised to the woman. “I deeply regret this episode and unreservedly apologize to the lady concerned for grabbing her, but in the current climate I felt the need to act decisively to close down the threat to the safety of those present,” he added.

At Thursday’s event, dozens of activists showed up wearing red suits, red dresses with sashes that said “climate emergency”, and then refused to leave. The video shows Field getting up from his chair and stopping a female protestor by pushing her against a pillar. He was also seen grabbing her by the neck and escorting her out of the room while the woman says “it was a peaceful protest”.

Greenpeace tweeted on Friday that the activist was doing fine. “She’s had a good sleep and is doing fine,” Greenpeace UK said. “We’re looking after her. Thanks so much for your love and concern everyone. We’re sharing positive messages with her.”

A spokesperson of the prime minister said that Field will remain suspended while the investigation is on. “The Prime Minister has seen the footage and found it very concerning,” a spokesperson told CNN. “The police have said they are looking into reports over this matter and Mark Field has also referred himself to both the Cabinet Office and Conservative Party.”

The spokesperson further added that the Cabinet Office’s propriety and ethics team would investigate whether there had been a violation of the ministerial code. The London Police said that it was looking into “a number of third-party reports of a possible assault” against the minister.

Opposition party leaders condemned Field’s actions with some calling for his resignation. “It is truly shocking to see this kind of behaviour from an MP,” Independent quoted London Mayor Sadiq Khan as saying. “Violence against women is endemic in our society and this behaviour is unacceptable. He should consider his position.”

However, some Conservative MPs defended their colleague. “I think there’s no reason to criticise Mark Field...Of course it wasn’t an assault, it was a reversal of direction,” said politician Sir Peter Bottomley.