Fariba Ahmadi Kakar and her three children were taken at gunpoint on Saturday in the central province of Ghazni on the main highway from Kandahar city to Kabul.
"The security forces released her children (two girls, one boy) in an operation yesterday. But she has been kept in another location, we are still searching for her," Mohammad Ali Ahmadi, deputy provincial governor of Ghazni, told AFP.
"The town elders are also involved in talks with the kidnappers to secure her release," he added, giving no further details about the identity of the kidnap gang.
Kakar's family earlier denied she had been taken hostage, with some relatives telling AFP she was in hospital.
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Taliban spokesman Zabihullah Mujahid told AFP that he was not aware of the kidnapping.
Hostages in Afghanistan are often taken by local criminal gangs, and can be sold on to insurgent groups who then demand cash ransoms or prisoner exchanges for their release.
Women who take on public roles in Afghanistan are constantly under threat, with many conservative Muslims against women working outside the home and building independent careers.
Lieutenant Islam Bibi, a well-known face of female advancement, was killed by unknown assailants when she was being driven to work by her son in the southern province of Helmand.
Women's rights are a key focus of international efforts in Afghanistan, with foreign diplomats often pointing to more female school children and greater freedom for women as signs of progress.
But donor nations have also raised fears that such advances are at risk as 87,000 NATO troops withdraw next year and Islamist groups lobby for more influence.