Video footage that appears to show MP Mike Amesbury punching a man to the ground is “shocking”, Sir Keir Starmer said as he defended Labour’s decision to suspend him.
The Prime Minister said the party had “moved very swiftly” to respond after the footage emerged.
Mr Amesbury was suspended by the party and lost the Labour whip on Sunday after a clip was published by MailOnline in which the Runcorn and Helsby MP is apparently seen continuing to hit the man lying on the ground as people nearby shout “Stop it”.
Sir Keir sidestepped a question about whether Mr Amesbury should resign as an MP but said: “I have seen the video footage, it’s shocking.
“We moved very swiftly to suspend him as a member and as a Member of Parliament.
“There is now a police investigation and in the circumstances you will appreciate there’s not much more I can say about that.”
Cabinet Office minister Pat McFadden declined to be drawn into commenting in any detail on the case to avoid possibly prejudicing it.
“The video is very graphic,” he told Sky News.
“The police will look into that. I’m sure they will take it into account.”
Asked if the party could be looking at a by-election in Runcorn and Helsby, he added: “Well I don’t know.
“Let’s see what the police say.
“They will be looking at all the evidence. What happened and they will reach a conclusion pretty soon I’m sure.”
Reform came second in the constituency at the general election with 7,662 votes to Mr Amesbury’s 22,358.
Labour said the Runcorn and Helsby MP had been suspended from the party “pending an investigation” into the incident.
It comes after footage obtained by the Mail Online appeared to show Mr Amesbury, 55, repeatedly hitting another man as others nearby shout “stop it”.
A Labour spokesperson said: “Mike Amesbury MP has been assisting Cheshire Police with their inquiries following an incident on Friday night.
“As these inquiries are now ongoing, the Labour Party has administratively suspended Mr Amesbury’s membership of the Labour Party pending an investigation.”
Cheshire Police confirmed a 55-year-old man had been voluntarily interviewed under caution in relation to the incident after officers were called to reports of an attack in Frodsham at 2.48am on Saturday.
“He has since been released pending further inquiries,” the force said.
CCTV published on Sunday captured two men standing facing each other before the man purported to be Mr Amesbury punched the other and continued hitting him on the ground.
It is not clear from the video what happened in the moments beforehand.
It comes after different footage posted on social media on Saturday appeared to show the MP shouting and pointing his finger at a man lying in the street.
“You won’t ever threaten me again, will you? You won’t ever threaten me again will you,” he appeared to say.
Mr Amesbury said he will “co-operate with any inquiries” but was “determined to remain an open and accessible MP for our community” after the initial footage circulated online.
He said in a statement: “Last night, I was involved in an incident that took place after I felt threatened on the street following an evening out with friends.
“This morning, I contacted Cheshire Police myself to report what happened during the incident.
“I will not be making further public comment but will, of course, co-operate with any inquiries if required by Cheshire Police.”
In July last year, a 56-year-old man was convicted of stalking the MP at his constituency office in Frodsham, where prosecutors said he was seen staring through the glass and asked guards about their level of security.
A Conservative Party spokesman said: “Mike Amesbury has questions to answer about his actions and it is right they are thoroughly investigated.”
