ISLAMABAD — Pakistani authorities released an ethnic Pashtun parliamentarian and civil rights leader hours after detaining him during a peaceful demonstration, a police official said on Wednesday, but more than 20 other demonstrators held with him remained in custody.

Mohsin Dawar, a sitting MP and a senior member of the Pashtun Protection Movement (PTM), was detained along with 23 supporters on Tuesday when he was leading a demonstration in Islamabad against the arrest of Manzoor Pashteen, chief of the group.

Dawar, who was also detained for months last year for allegedly inciting violent clashes with security forces during another protest, was released late Tuesday, a police spokesman said.

But a further 23 PTM members have been charged with incitement against state institutions including the powerful Pakistan military, disturbing law and order, and hate speech.

"All 23 ... will be presented before a magistrate today and will be sent to jail later," Zia Bajwa, spokesman for the Islamabad police, said.

The PTM have pressured the military since 2018 with calls to end alleged abuses by security forces targeting ethnic Pashtuns, including enforced disappearances and targeted killings, in the restive tribal areas along the border with Afghanistan.

The movement remains peaceful, but has been notable for its direct verbal attacks on the armed forces in a country where such criticism is largely seen as a red line.

Pashteen, the former veterinary student turned thorn in the military's side, was arrested on Monday in the northwestern city of Peshawar.

He is facing charges including sedition, hate speech, incitement against the state, and criminal conspiracy.

PTM leaders have called on their supporters to stay calm after Pashteen's arrest.

His lawyer Asad Aziz Mehsud said Pashteen has been remanded in the district of Dera Ismail Khan, and will seek bail on Thursday.