Sahar Gul, a 15-year-old girl severely tortured for months in a bid to force her into prostitution, will be sent to India for medical treatment.
In-laws who tortured Afghan child bride for months arrested
Sahar Gul's mother-in-law and sister-in-law were arrested and her husband was being sought, said the interior ministry spokesman, Sediq Sediqi.
The case has shocked Afghanistan, although rights activists have said serious abuses against women and girls are common.
Hamid Karzai, the president, has said that whoever used violence against Sahar would be punished.
According to officials in the north-east Baghlan province, the in-laws kept Sahar in a basement for six months, ripped her fingernails out, tortured her with hot irons and broke her fingers. Police rescued her last week.
The public health and women's affairs ministers visited Sahar, who is now in a Kabul hospital.
She was freed from a basement at her husband's home last week after her uncle called the police.
"It is a violent act that is unacceptable in the 21st century," Mr Sediqi said. "We are thankful of Sahar Gul's uncle."
He added that "if the police had not arrived in time she may have died".
Sahar was married about seven months ago. Jawad Basharat, a spokesman for the provincial police chief in Baghlan, said an arrest warrant had been issued for her husband, who is serving in the Afghan army.
"After police found out about the small girl, Sahar Gul, they took action and found her in the basement of the house in very bad condition," Mr Basharat said. "Her nails were pulled out, she has injuries in all parts of her body, there are signs of burning on her body, she was suffering from different kinds of injuries."
Mr Basharat said her mother-in-law and other members of the family were reportedly involved in "criminal activities", which he said included selling alcohol and prostitution.
According to preliminary reports, Mr Basharat said, "they tried to force her into prostitution and she did not agree. This was one of the reasons that they detained her in the basement for six months".
Rahima Zarifi, the provincial director of women's affairs in Baghlan, said a commission had been set up under Mr Karzai's orders to investigate the case.
"You can see the signs of torture and abuse all over her body, several types of torture and abuse. They even burnt her with hot irons," Mr Zarifi said. The health minister, Suraya Dalil, said that despite progress in women's rights, there was still work to be done.
"This is the very most extreme case we have seen ... that a girl child has been abused, has been physically abused, psychologically abused. It is an issue that shows we still need to work a lot with regard to education, with regard to awareness, with regard to social and economic development," Ms Dalil said.
Despite much progress since the fall of the Taliban 10 years ago, women's rights in Afghanistan remain a problem area in a country with a strict patriarchal culture.
A UN report in November found that a 2009 law meant to protect Afghan women from abusive practices, including rape, forced marriage and the trading of women to settle disputes, was being undermined by spotty enforcement.
The law was passed in August 2009 and criminalised many abuses for the first time, including domestic violence, child marriage, driving a woman to suicide and the selling and buying of women.
But the report found only a small percentage of reported crimes were pursued by the government.