(CNN) UK Prime Minister Theresa May has suspended senior politician Mark Field from office after video emerged of him grabbing and manhandling a protester at an event in London on Thursday evening.

"The Prime Minister has seen the footage and found it very concerning. 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 Prime Minister's spokesperson told CNN.

"He will be suspended as minister while the investigation takes place," the spokesperson added.

The Conservative Party lawmaker was at a black tie event at the Mansion House on Thursday when protesters from Greenpeace UK, dressed in red and wearing sashes with the words "climate emergency," interrupted a speech by the UK Chancellor, Philip Hammond.

During the protest, footage shows, one woman walked past where Field was sitting, at which he got up from his seat and grabbed her around the neck, pushing her against a nearby pillar. After a brief scuffle, Field is seen leading the woman out of the room by the back of her neck.