Pakistani intelligence officials say the leader of the Pakistani Taliban, Hakimullah Mehsud, may have been killed in a January 12 U.S. drone strike in the North Waziristan tribal region.

The unnamed officials said Sunday they have intercepted wireless radio conversations of the Taliban fighters discussing whether their chief was killed in the attack. Some of the overheard militants confirmed Mehsud was dead, while at least one criticized them for talking about it on the radio.

There was no official confirmation from Pakistan, and the Taliban issued a denial.

The news coincided with a bomb blast in central Punjab province that killed at least 16 people and wounded more than 20 others. Pakistani officials said the bomb ripped through a Shi'ite Muslim procession in Rahim Yar Khan district, marking the end of 40 days of mourning for the 7th century death of Imam Hussein, the grandson of the Prophet Muhammad.

There was no immediate claim of responsibility.

Shiites make up about 20 percent of Pakistan's mostly Sunni Muslim population of 160 million people. Shi'ite processions are often targeted by Sunni Muslim militants who view Shiites as heretics.