PSNI Serious Crime Branch detectives have charged a man in relation to the murder of prison officer David Black.
The 36 year old man was detained in Co Tyrone on Monday during a planned intelligence-led search.
On Wednesday night he was formally charged at Antrim Serious Crime Custody suite with terrorist-related offences.
He is due before Lisburn Magistrates Court on Thurday morning under heavy police guard.
The suspect was one of three people arrested by the PSNI and Garda detectives investigating the murder of David Black on the M1 motorway near Lurgan last month have arrested three people north and south of the border.
In a second planned operation, Gardai from the Special Detective Unit arrested a 31-year-old woman and 44-year-old man in Dublin in connection with the murder of David Black.
He is believed to be a former Provisional IRA sympathiser and Gardai suspect he may have supplied the Dublin-registered Toyota Camry car used in the murder.
Mr Black, a father of two was shot and killed as he drove to work at Maghaberry prison in Co Antrim.
A number of other people have been arrested in Lurgan, Tyrone and Co Leitrim but all were released without charge.
The most high profile of the arrests was Lurgan dissident Colin Duffy. He is to sue the PSNI for wrongful arrest and unlawful detention.