A pensioner arrested over a notorious bomb attack on a Belfast bar that killed 15 people has been released unconditionally, the Police Service of Northern Ireland (PSNI) said.
The 69-year-old man had been detained in Co Antrim for questioning this morning about the McGurk's Bar bombing of 1971.
It follows a PSNI review of the historic case in the wake of a critical 2011 report by the Police Ombudsman that highlighted wrongdoings in the original Royal Ulster Constabulary (RUC) investigation.
Officers said the review had identified "investigative potential".
The examination by the ombudsman's office found the RUC exhibited an ''investigative bias'' by claiming the loyalist attack was actually a republican bombing.
The bombing was carried out by the UVF, but had initially been presented by the RUC as an accidental ''own goal'' by the IRA, prompting speculation that the dead might have included IRA members who were carrying the device.
Bereaved families hailed the Ombudsman's report as delivering vindication for their loved ones, but denounced PSNI chief constable Matt Baggott for not accepting the claim that an RUC bias might have been at play in 1971.