Afghan police have arrested two men accused of beheading a teenage girl with a knife in northern Kunduz province, officials said on Wednesday.

Prior to the attack, the girl's father had rejected a marriage proposal for his daughter.

"Our investigation shows those who killed her were people who wanted to marry her," police told the BBC.

Earlier this month, four policemen were jailed for 16 years for raping a young woman in the same province.

In the latest incident, the girl, who was about 14 years old, was carrying drinking water from a nearby well to her house in Imam Sahib district when she was attacked on Monday.

"People were harassing the family and asking for her hand. When she refused, they did this to her," a police official told the BBC.

Senior Afghan officials and local tribal elders said the two suspects were close relatives of the girl.

The father had not wanted his daughter to get married because she was "too young to be engaged", he was quoted as saying by the Pajhwok news agency.

Details of the killing remain unclear and there are conflicting reports about exactly what happened.

On Thursday, the head of the women's affairs department in the province, Nadarah Gaia, said the girl may have been shot, rather than beheaded.