The younger brother of Afghan Taliban chief Hibatullah Akhundzada was said to be among at least four people killed in bomb blast at an Islamic seminary in a southwestern part of neighboring Pakistan.

Insurgent sources confirmed to VOA that the man, identified as Ahmadullah Akhundzada, was leading Friday afternoon prayer at the seminary's mosque in the Kuchlak area near Quetta, the capital of Baluchistan province, when the bomb went off.

There were no immediate claims of responsibly for the attack in a Pakistani province, which has long served as a hiding place for Taliban leaders and fighters waging a deadly insurgency against U.S.-backed government in Afghanistan.

A senior Pakistani regional police officer, Abdul Razzaq Cheema, told reporters the blast wounded more than 24 worshipers. The improvised explosive device, he said, was planted under the chair of the prayer leader and a timed device was used to trigger the explosion.

The police officer, however, shared no further details about identities of the victims.

Taliban spokesman, Zabihullah Mujahid, was not immediately available to comment on the reported death of the brother of Hibatullah, who himself also used to run an Islamic seminary, locally known as madrassa, in Kuchlak before becoming the chief of the insurgent group in 2016.

Hibatullah's predecessor, Mullah Akhtar Mansoor, was also killed in Baluchistan in 2016 in an American drone attack while he was returning from neighboring Iran and travelling through the Pakistani province.

The United States has long blamed Pakistan for not preventing insurgents from using its soil to plot attacks in Afghanistan. Pakistani officials maintain insurgents take shelter in areas hosting camps for millions of Afghan refugees in the country.

The relationship between Washington and Islamabad, however, has improved in recent months mainly because Pakistan is credited for arranging ongoing U.S.-Taliban peace negotiations aimed at ending the 18-year-old Afghan war.