Four members of the Sinn Féin Assembly team have said they will not be going forward for re-election amid heightening tensions inside the party over policing.
Former party members have also said they are being threatened to stay silent amid concern over the current political direction.
The decision on Wednesday by deselected assembly member Davy Hyland to become an independent left the Adams/McGuinness leadership facing a potential challenge in Newry and Armagh and possibly Mid Ulster.
Mr Hyland said: “I leave secure in the knowledge that I remain true to my republican principles.”
The Business Committee at the Belfast Assembly was informed of his decision, which relegates Sinn Féin to the third largest grouping with 23 Assembly members, behind the two main unionist parties.
Mr Hyland, who was sidelined over the holiday season, said he had reluctantly concluded there was no longer a place for him in Sinn Féin.
He said there was a limited timeframe for the public to have its say on policing.
“There’s been some discussion within Sinn Féin, but I don`t think the wider community, the people who actually elect Sinn Féin representatives, I don`t think they have been consulted enough,” he told BBC radio.
He accused the party of failing to practise what it preaches on equality,
“When I joined it (Sinn Féin) in 1981 it certainly was a very democratic party.
“Perhaps as time goes on maybe power becomes too centralised and individuals are given too much power.”
In a joint letter, John Kelly, a former Assembly member and founding member of the Provisional IRA, and Brendan “The Dark” Hughes, a leader of the first hunger strike inside the H-Blocks, hit out at what they said were ‘threats’ coming from Sinn Féin and directed against republicans who seek a wider debate on the policing issue.
“A number of people have been warned by Sinn Féin that they must not attend independent meetings organised by republicans around the policing issue.”
“It is the possibility of republicans fed up with Sinn Féin lies and deceit deciding to mount an electoral challenge that sends shudders of anxiety through the leadership circles.”
A Sinn Féin spokesman rejected the allegations, describing them as absolute nonsense. “A number of Sinn Féin members have attended these meetings.”
* Other Assembly members who will not be standing for Sinn Féin in a forthcoming Assembly election include Armagh woman Pat O’Rawe, who was deselected alongside Davy Hyland at a constituency meeting last month.
However, Sinn Féin officers are said to be considering re-instating Ms O’Rawe.
North Belfast Kathy Stanton and Mid-Ulster Assemblywoman Geraldine Dougan will also not be going forward. Ms Stanton denied the decision had anything to do with policing, but Ms Dougan has publicly voiced concerns about Sinn Féin supporting the PSNI.
Meanwhile, Sinn Féin’s Derry-based Mitchel McLaughlin is to contest the Assembly elections in the South Antrim constituency, replacing party veteran Martin Meehan. McLaughlin will attempt to win representation for the party in South Antrim for the first time.
Raymond McCartney, Lynn Fleming and Martina Anderson have been chosen to contest McLaughlin’s former Foyle constituency.