They were being questioned at Musgrave Police Station in Belfast.
A man and woman arrested in connection with the murder of Michael McGibbon have been released unconditionally.
The father of four died from his injuries after he was shot in the leg in Butler Place in Belfast in April.
Woman charged over theft of campaigner’s car ‘must stay out of Belfast’
Bluetongue restrictions in Northern Ireland will be relaxed from Friday
Conviction led to safeguarding review at Presbyterian Church
Coroner vows to keep Noah Donohoe inquest ‘on track’ for January start date
Appeal to European Court being considered after ruling over Troubles disclosures