ISLAMABAD (AP) — Amnesty International has urged Pakistan to release a Pashtun rights activist who was detained upon her arrival in the country.

The London-based rights group condemned the arrest of Gulalai Ismail, who was detained as soon as she arrived at an Islamabad airport from London.

In a statement, Amnesty International said she was being "detained solely for her peaceful human rights work".

Ismail is a critic of the Pakistani military's operations in the country's tribal regions in which many innocent civilians have been killed.

She has been a supporter of the Pashtun Protection Movement, a group which denounces perceived high-handedness by security forces and their operations in the country's northwestern regions. It calls for judicial probes into those killed by the military in the name of its war on terror.