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...