Loyalist blogger Jamie Bryson is set to be arrested by police over allegations that Sinn Fein "coached" him before he gave evidence to Stormont's Nama inquiry.
Detectives from the PSNI's Serious Crime Branch have asked several individuals to present themselves voluntarily for questioning as part of their investigation into alleged misconduct in public office.
It is understood Mr Bryson will refuse to voluntarily attend a police station for questioning and that he will then be arrested.
The allegations of misconduct in public office are based on leaked Twitter messages between Mr Bryson, former Sinn Fein MLA Daithi McKay, and party worker Thomas O'Hara.
The correspondence took place before Mr Bryson appeared at Stormont's Nama inquiry in September 2015. Sinn Fein has said that any individuals who may have been involved in communicating with the loyalist were acting alone and that the party had no knowledge of any messages to him.
Mr McKay resigned as North Antrim MLA after the messages were made public last August. A Sinn Fein councillor and 17 party activists resigned from the party in protest at how he had been treated. In an interview with this newspaper last month, Mr McKay announced that he had left Sinn Fein. The former MLA said that he had "moved on" since his resignation. He is now beginning to carve out a role for himself as a political commentator.
Mr Bryson said that detectives had originally been treating him as a witness in the investigation but that this had now changed to suspect status because he had refused to hand over relevant material to them.
Last night Mr Bryson said: "It is up to the PSNI how they conduct their investigation. I asserted journalist privilege and they are now treating me as a journalist. So in order to seize my phone and online communication, they have changed my status to that of a suspect. I will continue to assert my journalistic rights.
"The PSNI should think carefully before their next move as they are treading a very dangerous legal path."
It is expected that the loyalist will be arrested over the coming weeks. The Belfast Telegraph has been told that other individuals approached by detectives have voluntarily agreed to attend a PSNI interview.
Detective Superintendent Kevin Geddes of the PSNI Serious Crime Branch said: "As there is an ongoing police investigation it would be inappropriate to comment further at this time."
The Stormont finance committee inquiry, chaired then by Mr McKay, was set up in 2015 due to political controversy over the multi-million pound sale of Nama's Northern Ireland property portfolio. Nama is the Republic's 'bad bank', set up to deal with toxic loans after the 2008 property crash.
The Stormont inquiry was established following allegations in the Dail by Mick Wallace TD that a politician or political party in Northern Ireland stood to profit from the loan sale.
Mr Bryson used a meeting of the finance committee to name former DUP leader Peter Robinson as the individual he referred to as Person A in relation to the scandal.
Mr Robinson has strongly denied that he had sought to benefit in any way from the multi-million pound property deal.
It is now claimed that Mr McKay and Mr O'Hara advised Mr Bryson about his evidence before the hearing.
Leaked social media messages showed on September 17, 2015, Mr McKay sent a direct message to Mr Bryson, telling him to follow a Twitter account in Mr O'Hara's name. The following day a direct Twitter message from Mr O'Hara to Mr Bryson said: "You may only get 10-15 seconds on this before Daithi as chair has to pull you on it so squeeze your best points on this into 1-2 lines and come straight to the point."
Another message from him said: "Keep it short if you can, when it's said, it's said and it's privileged. Will be a great finisher."