Image caption Heidi Alexander, Liz Kendall and Lillian Greenwood are among those who have written to Jeremy Corbyn

Over 40 female Labour MPs have written to party leader Jeremy Corbyn urging him to do more to tackle abuse of MPs.

The letter highlighted an "extremely worrying trend of escalating abuse and hostility" towards MPs in recent weeks.

Women were disproportionately affected by these "disgusting and totally unacceptable" incidents, it said.

Leadership rival Owen Smith has accused Mr Corbyn of not doing enough to clamp down on "intolerance and misogyny". Mr Corbyn has condemned harassment.

The MPs' letter said: "Rape threats, death threats, smashed cars and bricks through windows are disgusting and totally unacceptable in any situation.

"This is acknowledged by all factions yet the simple words of condemnation offered in response are inadequate. We expect swift and tangible action against those who commit such acts.

"We understand that the leadership does not have total control over those who choose to threaten and abuse others but that does not mean that more cannot be done to safeguard our female colleagues."

It continues: "We have also been alarmed to learn that our shadow chancellor and other members of the shadow cabinet have addressed rallies and events in which demonstrations outside MPs' offices and bullying at CLP meetings have been either actively encouraged or quietly condoned."

The letter asks Mr Corbyn to make three pledges including "an unequivocal statement declaring his support for all MPs, particularly women, and clearly condemning campaigning outside MPs' offices, surgeries etc".

It finishes: "Jeremy, this is being done in your name."

'Permissive environment'

Unite trade union leader Len McCluskey has, meanwhile, suggested in an interview with the Guardian, that the security services could be behind the abuse and intimidation of MPs on social media.

Mr McCluskey claims MI5 could be using "dark practices" to "stir up trouble" for Mr Corbyn, arguing that spies had infiltrated trade unions in the past, and that the truth about it had been suppressed for 30 years, under the rule on keeping classified documents out of the public domain.

Mr Smith distanced himself from the suggestion, saying at a campaign rally in Manchester: "I'm not sure that's entirely right."

All Labour constituency parties have been suspended for the duration of the leadership campaign amid ongoing turmoil while several MPs who oppose Mr Corbyn have accused his supporters in the Momentum group of trying to intimidate them and their staff.

Angela Eagle, who withdrew her own leadership bid earlier in the week, has suggested Mr Corbyn was "stirring" the trouble, telling the Daily Telegraph he had encouraged a "permissive environment" within the party and she now feared for her staff's safety.

The former shadow business secretary says her constituency office was vandalised last week.

She has said she is cancelling walk-in surgeries in her Wallasey constituency on police advice - although Merseyside Police said it had been her own decision to do so.

Media playback is unsupported on your device Media caption Smith: Corbyn 'should take responsibility' for abuse

Mr Smith said he agreed with Ms Eagle that Mr Corbyn had not taken nearly a firm enough line on evidence of intimidation, both on social media and elsewhere.

"I think Jeremy should take a little more responsibility for what is going on in the Labour Party," he told the BBC News Channel.

"After all, we didn't have this kind of abuse, intolerance, misogyny and anti-Semitism in the party before Jeremy Corbyn became leader."

He added: "It is not good enough for Jeremy to say he has threats too. I have had threats too and I am telling him 'it has got to be stamped out and we have to have zero tolerance' of this in the Labour Party.

"The truth is many of the people who are heaping abuse on people are Jeremy's supporters. It is just a fact that it is Jeremy's side of the argument that is engaging in this great volume of abuse."

'Swift and tangible' action

Mr Corbyn said he had spoken out against "any forms of abuse whatsoever in politics or public life" and had immediately contacted Ms Eagle after he learnt of claims a brick had been thrown through the window of her constituency office, which is being investigated by police.

Shadow chancellor John McDonnell said both he and Mr Corbyn had been the target of abuse themselves and the Labour leader had "moved heaven and earth" to try to stamp it out.

He called on Mr Smith to "stop attacking Jeremy personally".

Conor McGinn, the MP for St Helens North, told Politics Home he had been subjected to a "torrent of abuse" by the Labour leader's supporters in recent weeks but his claims have been denied by the party leadership.

Media playback is unsupported on your device Media caption Corbyn 'regrets Eagle's language'

And more than two thirds of Labour's women MPs have called on Mr Corbyn to take "swift and tangible" action against those engaging in threatening behaviour which they say has caused them and their staff "severe distress".

The signatories - including former shadow ministers Heidi Alexander, Paula Sherriff and Kerry McCarthy - said campaigning outside MPs' homes and offices and bullying at constituency meetings should be condemned rather than "quietly condoned".

Mr Corbyn said he had spoken out against "any forms of abuse whatsoever in politics or public life" and had immediately contacted Ms Eagle after he learnt of claims a brick had been thrown through the window of her constituency office, which are being investigated by police.

The Labour leader, who launched his official re-election campaign on Thursday, said he had put in place a "very clear" code of conduct for how he and his supporters should behave during the two-month leadership contest - to be decided on 24 September.

He said: "I have made it clear that harassment and abusive language have absolutely no place in our political discourse.

"I receive plenty of abusive language and I do not respond to it any way because I don't want to demean myself or promote the person who is using that kind of abusive language. I think we should lower the temperature and increase the quality of our debate."

Mr Corbyn will seek to galvanise his own supporters at a series of UK-wide meetings on Saturday - with rallies in Salford, London, Bristol, Nottingham, Birmingham, Liverpool, Hull, Glasgow and Cambridge.