SPANISH police were last night reported to be holding an Irishman on suspicion of stabbing two women to death in their Costa del Sol homes.
Leading Spanish TV station Telecinco described the suspect as Irish.
Last night speculation was mounting that detectives were treating him as a suspected serial killer and looking to link him to a series of other unsolved murders across the country.
Detectives established a link between the deaths of two women reported to have worked as prostitutes advertising their services through papers.
A 45-year-old Spanish woman of Argentine origin was found in her luxury apartment in the Costa del Sol resort of Calahonda on August 11. She had been stabbed 15 times.
A month later, police discovered the body of a 47-year-old Ecuador-born woman at her rented home near Marbella. She had bled to death after being stabbed up to 12 times in her chest and neck.
Due to the investigating judge granting a secrecy order on the case, spokesmen from Spain's National Police and Civil Guard were unable to confirm the name and nationality of the suspect or discuss local media reports he had been carrying false ID when he was arrested.
A spokesman for the National Police said: "I've seen the reports suggesting the suspect is Irish and I've also seen other newspaper reports he's from central Europe, but I cannot give you any details about the man who is in custody."
His Moroccan girlfriend and her mother were also being held.
The man being held in custody was arrested on Friday at a gym near his home in Riviera del Sol near Fuengirola.
The block where he was arrested is just a stone's throw from the home of missing Amy Fitzpatrick's mum, Audrey.
Police are believed to have arrested him after stolen credit cards belonging to one of the victims was used to withdraw cash from ATMs in the area.