An alleged IRA informer is reportedly under round-the-clock guard after his name was published in the newspapers. What will life be like for the man on the run from the former comrades he is said to have betrayed?
That a man entrusted by the IRA to root out, interrogate and eliminate informers could have himself been leaking damaging information to the British authorities is a major blow to the paramilitary group.
Alfredo Scappaticci was named as "Stakeknife"
Given that the so-called Nutting Squad Alfredo Scappaticci allegedly led in uncovering IRA traitors is credited with a string of gruesome executions, it seems logical that his own acts of deception now make him a target for violent retribution.
So what can be done to protect Scappaticci - codenamed Stakeknife - if his cover has been blown?
Stakeknife's current whereabouts are a mystery. One Daily Mirror reporter says he interviewed Scappaticci at his Belfast home, and was told the whole affair a case of mistaken identity and that the 59-year-old would not flee. The house is now reportedly empty.
The British security services have not commented on this case, but are always tip-lipped about the arrangements made to protect witnesses and informants.
However, several stories have emerged from people who have been assisted by the authorities in hiding from danger. Many of these tales suggest Scappaticci and his family face a considerable ordeal.
Dr Nick Fyfe has examined the protection programme run by police in Strathclyde. He says the "social and psychological pressures" which accompany the resettlement of witnesses and informants make such programmes a solution of "last resort".
Stakeknife was supposedly at the heart of the IRA
Those seeking to evade murderous revenge attacks must first utterly abandon their former homes - often at very short notice.
One fleeing witness says he was asked by his police handlers to pick a new and distant region to live in, and then quickly found himself in a flat - with second-hand furnishings - "where you would not put your worst enemy".
Stakeknife is said to have been handsomely paid by masters, but many of those going into hiding do so without such funds at their disposal.
No life of luxury
"These programmes aim to offer like for like, so that it doesn't appear to juries that witnesses have been financially rewarded for testifying. Those in hiding don't see an improvement in their standard of life," says Dr Fyfe.
What they are guaranteed is a life rich in anxiety. "The fear of being discovered is constant, when a letter drops on the mat, when a car pulls up outside, when the phone rings," says Dr Fyfe.
Since cosmetic surgery is only likely to be available in the most extreme circumstances, even walking to the shops can be a terrifying prospect for those keenly aware of the consequences of being recognised.
Even a busy street promises peril
These stresses must be faced in an unfamiliar setting and often without the kind of support from friends and family that ordinary people take for granted.
When an individual or a family is relocated, security dictates that their isolation from their previous life must be total, for fear that maintaining any contact with relatives or old associates will allow the hiders to be tracked down.
"Creating new relationships in the new area is also fraught with difficulties. Part of building friendships involves talking about our pasts, this is very hard when you have had to assume a false identity."
Inventing a past
As well as providing their charges with new names, passports and other documents, police handlers also help them to construct believable biographies which will stand up to scrutiny and not inadvertently reveal their true history.
Dr Fyfe says such provisions have improved in recent years as the authorities "have learned from their mistakes".
Martin McGartland - an IRA informer whose cover was blown in 1991 - later saw his assumed identity reduced to tatters when a speeding offence put him in the dock and his string of falsified driving licences was publicly examined.
Martin McGartland's new indentity was revealed
In 1999, McGartland survived a serious gun attack, in which he was shot six times in the stomach.
The majority of protected witnesses, informants and so-called "supergrasses" are useful to the authorities precisely because of their criminal pasts. False documents and new names often cannot fully erase the legacy of these previous lives.
Though relocated, says Dr Fyfe, some of those in hiding can revert to their former criminal activities.
The Witness Protection Program in the United States - the model for schemes in the UK and across the world - has unwittingly aided thieves, drug dealers and murderers.
One of the most notorious was Marion Pruett, an inmate released from an Atlanta prison for testifying against his cellmate. Resettled, Pruett went on a killing spree which left six dead.