Feuding loyalist paramilitaries were behind a bomb attack on a house in Derry, it was claimed tonight.
Five people escaped injury when the device exploded at the rear of the property in Bond's Place.
The pipe-bomb attack, which caused minor damage, followed a row at a pub in the area at the weekend.
Sources said tonight the dispute was linked to simmering divisions between Ulster Defence Association and Ulster Volunteer Force factions.
One claimed: "Police believe it's the UDA and UVF at each other's throats."
As security was heightened amid fears of reprisal attacks, it emerged that one of the five people who were in the house has fled the city.
It is understood he was in the bar when trouble broke out after the annual Apprentice Boys' parade through the city on Saturday.
Police have confirmed the pipe bomb is similar to devices used by loyalist terrorists in attacks across Northern Ireland.