A teenage girl was beheaded by a relative in northern Afghanistan after she turned down his marriage proposals, according to reports.The victim, named as Gisa, was decapitated with a knife in the Imam Sahib district of Kunduz province on Tuesday, local police said. She is believed to be around 15-years-old.A police spokesman said two men, named as Sadeq and Massoud, had been arrested following the teenage girl's murder.The two men are understood to be close relatives of the victim that live in the same village.Local police sources have said the men behind the attack wanted to marry the girl, but their advances had been turned down by victim's father.Gisa is understood to have been attacked as she returned to her home in Kulkul village after going out to collect water from a nearby well. Her father told a local news agency he had not wanted his daughter to get married because she was too young. Afghanistan's Taliban regime - notorious for its oppression of women in the country - was ousted in 2001, but extreme violence against women is still rife. In 2009 the Elimination of Violence Against Woman law was introduced in Afghanistan, criminalizing child marriage, forced marriage, 'giving away' a girl or woman to settle a dispute, among other acts of violence against the female population of the ultra-conservative Islamic nation.But the UN has said there is a 'long way to go' before the rights of Afghan women are fully protected.While Afghan women have won back some basic rights since the Taliban was toppled 11 years ago, so-called honour killings remain relatively commonplace in the war-torn Islamic nation.