The bodies of 60-year-old Arouba Barakat and 23-year-old Halla Barakat were discovered in their home in Istanbul in September. Police later arrested a cousin, Ahmet Barakat, who prosecutors charged with murder.
Anadolu Agency said the Istanbul court on Tuesday convicted Barakat of murder and sentenced him to two life terms without parole.
Anadolu said that Barakat initially confessed to killing his cousins after a fight over money, but later denied involvement.
He claimed during Tuesday's hearing that he had been misled by an interpreter who told him he would get a light sentence if he confessed, according to Anadolu.
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