PESHAWAR -- Police in Pakistan have detained the leader of a civil rights group that has criticized the military's operations in the northwestern tribal regions.

Manzoor Pashteen, leader of the Pashtun Protection Movement (PTM), was taken away by officers in the city of Peshawar overnight, police told RFE/RL on January 27.

Pashteen is accused of sedition, hate speech, incitement against the state, and criminal conspiracy after a rally organized by the PTM attracted thousands of people in the city of Bannu on January 12.

He has not been formally charged yet.

Mohsin Dawar, a Pakistani lawmaker and a PTM member, called Pashteen’s detention "punishment for demanding our rights in a peaceful and democratic manner."

"But Manzoor's arrest will only strengthen our resolve," he wrote in a tweet.

Amnesty International South Asia said Pashteen has been "arbitrarily detained for exercising his human rights to freedom of expression and peaceful assembly. He must be released immediately and unconditionally."

The PTM has campaigned for civil rights for ethnic Pashtuns since 2018. The group has attracted tens of thousands of people out to public rallies to denounce the powerful Pakistani army's heavy-handed operations in the militancy-hit tribal regions and the military's alleged connection with Islamist militants.

The military has accused Pashteen of treason by criticizing the army falsely.