A key electoral town's Labour group is "at war with itself", it has been claimed.
The Redcar and Cleveland Council Labour Group was reviewed by the party in 2012 after complaints of bullying and physical intimidation between members.
But branch members said the situation had now become even worse.
Labour North said changes were already being made, with the party keen to win the constituency back from the Liberal Democrats in the General Election.
Labour includes Redcar as one of its 106 key battleground seats. It had held the constituency since it was created in 1974 until the Liberal Democrats won with a majority of more than 5,000 in 2010. Mo Mowlam, Northern Ireland Secretary in Tony Blair's first cabinet, was Redcar's MP from 1987 until 2001.
Darlington Labour councillor Nick Wallis wrote a report in 2012 that has never been published but has been seen by the BBC. It found party meetings often descended into chaos with group members reduced to tears.
He concluded the situation needed urgent resolution ahead of the election in May.
But Redcar Labour councillor Steve Goldswain, who was deselected as a candidate for the May council elections by the party, said the situation had worsened since the Wallis report.
He said: "The party in Redcar has gone to war with itself, it's almost akin to North Korea, anonymous reports are written about members but they won't tell you why you're being investigated, they just hand out the punishments."
The BBC understands a number of other members also have concerns.
'Robust but fair'
A spokesman for Labour North said: "Since this report was written The Labour Party has worked to implement a number of changes in the way the group operates.
"We expect the highest standards (from members) including a commitment to campaigning for the party and engaging with the local communities all year round."
The spokesman also said the selection process for election candidates had been "robust but fair". No details about the changes or action taken have been given.
The Wallis report said it was "unacceptable" on both sides that Middlesbrough South and East Cleveland MP Tom Blenkinsop, also a Labour member, was filing Freedom of Information requests to the Labour-run Redcar council as he had "no faith in the party's usual communication channels".
Mr Blenkinsop declined to comment.