A furious row has erupted at the top of the Labour Party after a member of the shadow cabinet claimed she had been the victim of a "bullying culture of the worst kind".
Debbie Abrahams hit out after the party announced she had "stood down" as shadow work and pensions secretary while she was investigated over an "employment issue".
In a bombshell statement she rejected the allegations against her in the "strongest possible" terms and warned that she had not ruled out legal action.
She then turned her fire on Jeremy Corbyn, accusing "certain individuals" in the leader's office of "aggressive, intimidating and wholly unprofessional" treatment over the past 10 months.
"My treatment in the last week has shown a bullying culture of the worst kind. As such I am making a formal complaint to both the Labour Party and Parliamentary authorities," she said.
Debb Her angry onslaught followed a statement from the party saying she had "stood aside from her frontbench role while the Labour Party investigates an employment issue".
It added that her deputy Margaret Greenwood would act as shadow secretary of state for work and pensions while the inquiry was carried out.
No details were given of the allegations against her although Labour sources let it be known that there had been a number of complaints.
However Mrs Abrahams insisted that she had not agreed to stand down and said she had been told nothing of any complaint against her.
"I refute the allegations that have been made against me in the strongest possible terms," she said in her statement.
"I will fight this spurious claim and do not rule out taking legal action.
"I have had no details about the complaint, who it is from, the process or timescales. I have not agreed to stand aside."
The stand-off threatens to trigger the worst crisis in Mr Corbyn's leadership since the mass shadow cabinet resignations following the EU referendum in 2016.
Since he was first elected leader in 2015, there have been repeated complaints - particularly from Labour women - of bullying and intimidation by his left-wing supporters.
Mrs Abrahams first entered Parliament in 2010, winning the Oldham East and Saddleworth by-election after the election of Labour MP Phil Woolas was ruled void over false statements he made about a rival candidate.
She was made shadow minister for the disabled by Jeremy Corbyn in 2015 and was promoted to the shadow cabinet after last year's general election.