Journalist and former British MP Chris Mullin has named, for the first time, two of the men he says carried out the Birmingham Pub bombings in 1974.
21 people died and scores were injured when two bombs - widely blamed on the IRA - exploded in the Tavern in the Town and Mulberry Bush pubs in the centre of the city.
A resumed inquest into the 21 deaths is due to get underway later this month, following a long campaign by some of the families of those who died.
The campaigners had wanted the scope of the inquest to include an examination of who was responsible for the blasts, but the coroner ruled that was outside the remit of his inquest.
Six Irish men - who became known as the Birmingham Six - were wrongly convicted of the atrocity and served 16 years in prison before their convictions were overturned.
Chris Mullin had campaigned for the release of the six men and carried out an investigation into who was responsible for the bombing. It formed the basis of a TV documentary and book called 'Error of Judgement'.
Today, writing in the London Review of Books, Mr Mullin names two men - Michael Murray who died in 1999 and James Francis Gavin who died in 2002 - as among those he believes responsible for the bombs.
Mr Mullin says he longer has "any compunction about identifying two of the men involved, who are now dead … but the man described in my book as the 'young planter' is still alive, and I will not name him".
He says he "interviewed many of those who were active" in the IRA's West Midlands campaign.
"To gain their cooperation I gave repeated assurances, not only to the guilty, but to innocent intermediaries, that I would not disclose their identities. I cannot go back on that now, just because it would be convenient. My purpose at the time was to help free the six innocent men who had been convicted of the bombing."
