Image caption The 20-year-old woman is recovering in hospital

Police in central Afghanistan are searching for a man who allegedly cut off part of his wife's nose with a kitchen knife.

The woman, thought to be 20, is in hospital. Officials say the man has reportedly assaulted his wife before.

Although such mutilation is rare in Afghanistan, reports of violence against women are increasing.

Last year the country's Human Rights Commission said violence against women rose by almost 25%, compared with 2012.

The names of the couple have not been released but police in Daykundi Province say the man attacked his wife after a heated argument.

"The husband cut his wife's nose with a kitchen knife," said Muhammad Ali Atai of the Provincial Crime Branch in Daykundi.

"Police transferred her to hospital. But her husband escaped from the area and is still at large."

The woman's family has not commented on what happened and details are sketchy.

'Removed her fingernails'

Zakia Rizai, the head of Daykundi's Women's Affairs Department, told the BBC that the woman had been the victim of severe domestic violence in the past.

"Her husband was a violent man," she said. "We saw evidence that he had removed her fingernails. Once, she was kept locked inside a room without food or water for a week."

Cases of women being mutilated by male relatives are rare in Afghanistan but not unknown.

Last year, the BBC reported on the case of a 30-year-old woman called Sutara in Herat who spoke to reporters from her hospital bed.

She said she became engaged to her husband when she was just 11 and that he became addicted to heroin while working across the border in Iran.

Her husband wanted to sell her jewellery to buy drugs, she says. When she refused to hand it over to him, he knocked her unconscious, then stabbed her and cut off her top lip and her nose with a knife.

This latest case comes against a background of growing violence against women.

One reason behind the increase could be that more women are reporting abuse and the media is more likely to report their cases.

But analysts say many such crimes involving domestic violence still go unreported.

Some women are simply too frightened to speak out. Others may not trust the police to treat them fairly or have confidence that the justice system will support them if they do.