Mark Field has been suspended as a minister after TV footage showed him grabbing a female Greenpeace activist at a black-tie City event.
Mr Field, Foreign Office minister for Asia and the Pacific, has said he regrets the incident at the chancellor’s Mansion House speech.
He said he had been “genuinely worried” she may have been armed.
Mr Field was filmed forcibly removing the woman after protesters interrupted the speech.
City of London Police said they were looking into a “small number” of third-party reports of an assault at the Mansion House event.
Labour had called for him to be suspended or sacked.
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