PESHAWAR, Pakistan -- The Pakistani Taliban on Thursday backed out of peace talks with the government after confirming the death of its top military commander and deputy leader, Waliur Rahman, in a U.S. drone strike in the volatile North Waziristan tribal region.
"We are so sad to announce that our sincere and brave leader and a great mujahid [holy warrior], Maulana Waliur Rahman, has died in a U.S. drone attack on Wednesday. It's a huge loss for us," Taliban spokesman Ihsanullah Ihsan said, adding that the group plans "to take revenge."
The spokesman said that the group had withdrawn from peace talks with the Pakistani government and that it blamed the killing on the "Pakistani establishment" and the United States.
"We will teach a lesson to Pakistan and United States for depriving us of our beloved leader," he said.
Security in the capital, Islamabad, was beefed up after Rahman's death, with a senior police official in the city saying Thursday that the force was on "red alert" after fresh intelligence reports indicated "possible terror attacks."
Cars coming into the city were being stopped and examined at checkpoints, the official said.
Taliban sources said that besides Rahman, three other senior militant commanders were killed in the drone attack and two others were critically injured.
Ihsan said the Taliban would soon announce Rahman's replacement, though some Taliban sources said the militants had already chosen commander Khan Said to replace him.
The drone strike came just before Pakistan's newly elected government was set to take the oath of office.
Both Pakistan Muslim League-Nawaz (PML-N) and Pakistan Tehreek-e-Insaf (PTI), which emerged as the two most popular political parties in the recent general election, are opposed to U.S. drone strikes and pledged to stop the attacks if voted to power.
In a week's time, both parties will be in power and Nawaz Sharif's PML-N will be ruling Punjab and the center of the country while Imran Khan's PTI will be heading the coalition government in Khyber Pakhtunkhwa.
After Baitullah Mahsud and Qari Hussain, a TTP commander known as a mentor of suicide bombers, Rahman was the third senior Pakistani Taliban leader killed in a U.S. strike on Pakistani soil.
Rahman, a 42-year-old from South Waziristan, was considered a moderate in the TTP compared with some of his hawkish colleagues.
NBC News' Fakhar Rehman contributed to this report.
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