Actor Tony Robinson, known for portraying Baldrick in Blackadder, has come to the defence of Birmingham MP Jess Phillips after she said she no longer felt welcome in the Labour Party.
The star, a longstanding Labour activist who presented history show Time Team, said Ms Phillips was a victim of bullying.
And he said: "If people like the brilliant and dedicated Jess Phillips are being made to feel unwelcome in our party then something has gone badly wrong."
It comes after the MP said she sometimes wondered "why I would want to stay somewhere where I am so obviously not welcome."
In an interview with the BBC, she said: "I don't feel welcome from huge swathes of people from now the Labour Party. It would be wrong of me to say anything else.
"I every single day receive messages saying I am not good enough, that I should lose my job - and that’s the tamest stuff."
But the comments were seized on by some online critics of Ms Phillips who used them as an excuse to continue the abuse.
Listen: Jess Phillips says Labour leader Jeremy Corbyn incites abuse of MPs
In a comment on Twitter, Sir Tony, who was knighted in 2013, said something had gone wrong in the Labour Party if Ms Phillips felt unwelcome.
The actor then received a series of comments from people attacking Ms Phillips or objecting to his statement.
He said: "After 2 weeks on Twitter, I've upset the vegans & those who think it's fine to bully Jess Phillips. I apologise unreservedly to the vegans."
He told his followers: "Not just about Jess Phillips, it's about bullying as a political tactic. I saw the hard-left use it in the 80s. Heartbreaking that it's back."
And in what appeared to be a response to people who complained that other MPs also received abuse, or that Ms Phillips had simply made it all up, he said: "Imagine if your kid said they were being bullied, and the school denied it or said it was ok cos lots of other kids were being bullied too!"
The Labour leadership contest, in which Labour leader Jeremy Corbyn faces a challenge from rival candidate Owen Smith, has been marred by claims of bullying and intimidation.
On BBC's Victoria Derbyshire show on Wednesday, one Labour activist who supports Mr Smith said she would feel more welcome at a Conservative event than among Mr Corbyn's supporters.
