Eight members of the Labour Party in Northern Ireland have quit its executive committee.
The eight include the chair, vice chair and secretary of committee.
Kathryn Johnston, who is among those who have stepped down, said there was a "dysfunctional element" in the party's regional executive.
However, the new chairman said the committee rejected all the allegations of former committee members. Their positions have now been filled.
Those who resigned said they were stepping down due to concerns about "a small minority" who, they claim, support other political groups but are "secretly organising" within Labour.
The eight said the activities of those whom they term a "vocal and troublesome element" were contrary to the Labour Party's rulebook.
Ms Johnston, who is a former secretary of Labour NI, said they had taken the decision after five months of meetings.
Ms Johnston told Good Morning Ulster that administrators of the People Before Profit Facebook page were also Labour NI members - which is against Labour Party rules.
"Rules are rules, it is quite clear," she said. "Chapter two of the Labour Party rules [says] you can't be a member of two parties."
Boyd Black, chairman of Labour NI, said the resignations were made before an executive committee meeting on Monday night.
He said the meeting was called "after a number of grassroots party activists had indicated that they would attend in order to call the [former] EC members to account on a number of issues, including inactivity and lack of accountability".
He said the party remained "fully committed to Jeremy Corbyn's 'For The Many Not The Few' policy manifesto".
The resigning officers remain members of the Labour Party.
A spokeswoman for People Before Profit said: "We have no knowledge of any current members of People Before Profit who are involved at any level in the Labour Party of Northern Ireland.
"Reports of People Before Profit members involved in entryism into the Labour Party of Northern Ireland have come as a surprise to us."