Pakistani officials told the media that Sharbat Gula, the famous green-eyed Afghan girl, was arrested by Pakistan's Federal Investigation Agency (FIA) after a two-year probe in Peshawar, near the border of Afghanistan.

Pakistani authorities claim the arrest was due to having had a fake ID.

Gula allegedly applied for an identity card in April 2014, using the name Sharbat Bibi. If the fraud claims are true, she is one of thousands of Afghan refugees living in Pakistan who have tried to dodge its computerized system.

Gula was 12 when photographer Steve McCurry captured his iconic image of her living in a refugee camp for Afghan nationals in Peshawar, Pakistan. Her image was first used on the cover of National Geographic.

Now in her 40s, Gula -- also known as Sharbat Bibi -- was arrested in Peshawar on Tuesday for falsifying documents and staying illegally in Pakistan, officials said.

The UN Refugee Agency (UNHCR) in Afghanistan told CNN it would only be able to assist in the case if Gula registers as a refugee.

"Sharbat Gula falls under the 'undocumented migrants' umbrella," said Duniya Khan with the agency's Pakistan office. "The UNHCR cannot intervene since she is not a registered refugee."

The International Organization for Migration (IOM), which assists undocumented migrants, says the arrest -- although legal if the ID card is proven to be false -- is symptomatic of the mounting pressure on Afghan refugees in Pakistan to return home, according to CNN report.

"It is a sign of the times in Pakistan, that it has now reached someone who was something of a celebrity in the '80s, someone more high profile than the average," said Nicholas Bishop, project development officer for the IOM in Afghanistan.

Human Rights Watch (HRW) said since July 1, Pakistan has repatriated 370,000 Afghans, nearly 220,000 of them registered refugees.

Millions of Afghans have sought shelter in Pakistan over the years as their country became ravaged by conflict, HRW said.