Suspected agent Dennis McFadden may have fled his home in the outskirts of north Belfast a week before details of his activities emerged, neighbours say.
He is believed to have been central to the arrest of nine republicans and a Palestinian man over the last week.
The ten were detained as part of Operation Arbacia, which is investigating the activities of the 'IRA', which is often referred to as the New IRA.
Originally from Scotland, he is believed to have shared the home with his partner and young child.
The red brick house is located in a quiet cul-de-sac in Glengormley.
Hanging baskets in full bloom and a slightly overgrown front garden neatly disguise the property's sensational secrets.
Until last week the house was home to Mr McFadden, who is now believed to be under the protection of British intelligence.
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The property was empty yesterday with the white blinds drawn.
A child's scooter lay abandoned where it was left on a path close to the front door of the vacant property.
The suspicion of neighbours was raised last week when strangers arrived at the average suburban home.
It is understood two dark coloured vehicles, including a Transit van and a people carrier, pulled up at the house last Wednesday afternoon.
Locals say there was one person in each vehicle and at this point nothing was removed from the property.
It is understood both vehicles left the area shortly before a white removal van arrived in the sleepy street shortly after 2.30pm.
Within an hour the truck pulled out of the street laden with the contents of Mr McFadden's home.
However, one local said that the property was empty for around a week before the arrival of the removal truck.
One neighbour said that although Mr McFadden, who managed a bar in west Belfast, kept to himself there was a regular stream of visitors to the property.
It is reported that had installed a mini bar at the side of his house and regularly served himself and visitors pints of draught Guinness.
It has been suggested that at times he could work his way through two kegs a week, which were often delivered to the house by taxi.