SYDNEY: An Australian aid worker who was kidnapped in Afghanistan four months ago has been freed and is “safe and well”, Foreign Minister Julie Bishop said Monday.

Katherine Jane Wilson, who goes by the name Kerry and is reportedly aged around 60, was grabbed in the city of Jalalabad, close to the border with Pakistan, in late April.

She had been visiting the city for a women's embroidery project when gunmen abducted her, Ataullah Khogyani, a spokesman for the governor of Nangarhar province, of which Jalalabad is the capital, told AFP at the time.

He said she was taken before dawn from the home in which she was staying by “unidentified gunmen” who were disguised as police.

“I confirm that Kerry Jane Wilson, who was abducted in Afghanistan in April this year, has been released, and she is now safe and well,” Bishop said in a statement.

The minister, who has previously said Australia does not pay ransom for kidnappers, voiced relief for Wilson and her family but would not provide details of how she was freed.

“I deeply appreciate the work of the authorities in Afghanistan whose support and assistance facilitated her release, as well as Australian consular staff who continue to provide assistance to Ms Wilson and her family,” Bishop said.

But she added: “To protect those who remain captive or face the risk of kidnapping in Afghanistan and elsewhere, the government will not comment on the circumstances of Kerry Jane's release.”

No details were given in Bishop's statement of when Wilson was released or where she was taken to safety.

Wilson, who ran an organisation known as Zardozi, which promotes the work of Afghan artisans, and particularly women, was a well-known non-governmental organisation worker.

Aid workers have increasingly fallen casualty to a surge in militant violence in Afghanistan in recent years, with several abductions in recent months.

The Afghan capital Kabul is infested with organised criminal gangs who stage kidnappings for ransom, often targeting foreigners and wealthy locals, and sometimes handing them over to insurgent groups.

An Australian man was seized, along with an American colleague, in Kabul earlier this month by gunmen wearing police uniforms.

The two foreigners, professors from the American University of Afghanistan, were pulled from their vehicle after the kidnappers smashed the passenger side window and hauled them out.

Judith D'Souza, a 40-year-old Indian employee of the Aga Khan Foundation, a prominent NGO that has long worked in Afghanistan, was abducted near her residence in the heart of Kabul on June 9. She was rescued in July.

After the April abduction, Wilson's 91-year-old father Brian Wilson said his daughter had worked in the region with charities related to women's rights and water security for more than 20 years and was aware of the risks.

“I presume she's a hostage, and that they'll do their best to keep her alive and not harm her, simply because they want to have something or other in return and it's not very good having a dead hostage,” he told the Australian Broadcasting Corporation.