A man who beheaded his 17-year-old wife has been sentenced to eight years in prison in Iran, the judiciary says.Images of Sajjad Heydari carrying Mona"s severed head in Ahvaz after the so-called "honour killing" last year caused widespread outrage.A judiciary spokesman said the leniency of the sentence was due to Mona"s parents having "pardoned" him for the murder rather than seeking retribution.