Qamar Gul with AK-47 poses for a photograph at her home. File

Qamar Gul (right) and her brother Habibullah, 12, pose for photograph in the governor's office in Ghor province. AP

The incident happened last week when insurgents stormed the home of Qamar Gul, a teenager from a village in the central province of Ghor.

The fighters were looking for her father, the village chief, local police head Habiburahman Malekzada said.

Her father was a government supporter, which is why the Taliban fighters went to his house and dragged him out, Malekzada said.

When his wife resisted, the Taliban fighters killed the couple outside their home, Malekzada said.

"Qamar Gul, who was inside the house, took an AK-47 gun the family had and first shot dead the two Taliban fighters who killed her parents, and then injured a few others," he said.

Gul is aged between 14 and 16, according to different officials. It is common for many Afghans to not know their precise age.

Several other Taliban fighters later came to attack her house, but some villagers and pro-government militiamen expelled them after a gunfight.

Afghan security forces have now taken Gul and her younger brother to a safer place, said Mohamed Aref Aber, spokesman to the provincial governor.

Since the incident, social media networks have been flooded with praise for Gul's "heroic" act.

A photograph of Gul, wearing a headscarf and holding a machinegun across her lap has gone viral in the past few days.

"Hats off to her courage! Well done," wrote Najiba Rahmi on Facebook. "Power of an Afghan girl," wrote another Facebook user Fazila Alizada.

"We know parents are irreplaceable, but your revenge will give you relative peace," said Mohamed Saleh in his post on Facebook.

The Taliban regularly kill villagers who they suspect of being informers for the government or security forces.

In recent months, the militants have also stepped up their attacks against security forces despite agreeing to peace talks with Kabul.