Detectives hunting a gang who doused a couple in petrol and set them alight in Co Armagh last year have arrested a man.
The 25-year-old was being questioned in connection with the double murder of Lisa McClatchey (21) and her partner Thomas O'Hare (33) near Keady in November 2006.
The PSNI said the man was arrested in the Newry area late last night. And it is understood he is being detained at Ardmore PSNI station in the city.
Ms McClatchey and Mr O'Hare were beaten with hammers, covered in flamable liquid and then burnt alive at their home on Foley Road, Tassagh on November 6, 2006.
Their brutal killing horrified the people of Northern Ireland.
Police believe up to six men forced their way into their remote bungalow. Ms McClatchey managed to run from the house in flames and alerted neighbours.
Mr O'Hare was found by neighbours lying in the garden.
He died four days later in hospital.
Ms McClatchey, who was admitted to hospital with 80% burns, died just over a week later.
It is understood that Mr O'Hare was the main target of the attack.
At the time police would not rule out the possibility that the attack was carried out by self-styled vigilantes.
One man has already been charged in connection with the deaths.
In February Colum Smith (57) was accused of two counts of impeding the apprehension of offenders.
Mr Smith's four sons were treated in hospital in Dundalk after the attack.