The Pakistani Taliban appointed as its new chief Thursday a hard-line commander responsible for some of the country’s worst violence, including the recent assassination of a Pakistani general and the attempted killing of schoolgirl Malala Yousafzai last year.

After conferring for six days in North Waziristan, 17 members of the group’s governing council selected Maulana Fazlullah as the militant group’s new operational and tactical leader, Taliban spokesman Shahidullah Shahid said in a phone interview. Fazlullah replaces Hakimullah Mehsud, who was killed by a U.S. drone a week ago in an attack that brought vows of retribution and is complicating relations between the United States and Pakistan.

In choosing a figure whom some analysts describe as Pakistan’s most feared man, Shahid said the Taliban’s goal was to signal that its insurgency against the government will continue, despite Prime Minister Nawaz Sharif’s effort to engage the group in peace talks.

Fazlullah, who is thought to be living in eastern Afghanistan, was the Taliban commander in Pakistan’s scenic Swat Valley from 2007 to 2009, when the group effectively controlled the area. It attempted to impose harsh sharia law on residents, and those who resisted it were whipped, beaten, tortured or executed.

Fazlullah is wanted on 104 criminal charges in Swat but has evaded Pakistani security officials, NATO troops in Afghanistan and U.S. intelligence officials, despite several false reports over the years of his death in a drone strike.

Last year, Fazlullah ordered the execution of Yousafzai, 15 at the time, after she spoke out against Taliban attempts to prevent girls from going to school. Yousafzai, who was shot in the head on her school bus, recovered after being airlifted to England for treatment and was a nominee for the Nobel Peace Prize this year.

In early October, Fazlullah asserted responsibility in a video for killing a two-star Pakistani army general and two other military officials in a roadside bombing near the border with Afghanistan. The video infuriated Pakistani military leaders, many of whom remember Fazlullah from his fierce resistance to the 2009 military campaign to regain control of the Swat Valley.

Neither Pakistan’s government nor its powerful military commented Thursday on Fazlullah’s selection, but analysts say the development severely undermines Sharif’s efforts to hold peace talks. Those plans have been on hold since last Friday’s killing of Hakimullah Mehsud, who was wanted by the United States in connection with a 2009 assault on a CIA base that killed seven Americans and a 2010 plot to bomb Times Square in New York.

“From the Pakistani establishment point of view, [Fazlullah] is a very dangerous guy,” said Saifullah Mehsud of the Islamabad-­based FATA Research Center, which investigates terrorist organizations. “Through his acceptance of the killing of the army general and his cross-
border attacks, all of these things establish him as the most hated guy as far as the military is concerned.”

Fazlullah, thought to be in his late 30s, is known as “Mullah Radio” because he is frequently spotted with a transmitter used to relay music and messages. Fazlullah was raised near Mingora in the Swat Valley and became an avid follower of Sufi Mohammad, the detained founder of the radical Movement for the Enforcement of Islamic Law group, later marrying his daughter.

According to officials in the Swat Valley, Fazlullah took thousands of young men to Afghanistan to fight NATO troops there after the U.S-backed ouster of the Taliban in late 2001. In 2002, he returned to the Swat Valley, where he helped build a madrassa, or religious school, and launched a private radio station that he used to give sermons and solicit donations.

“Women donated their gold ornaments to Fazlullah,” one Swat Valley resident said in a phone interview, speaking on the condition of anonymity because of security concerns.

In 2007, Fazlullah used his radio broadcast to denounce Pakistan’s then-ruler, Pervez Musharraf, after the military stormed the Red Mosque in Islamabad to flush out Islamic students who had sought refuge inside. The incident prompted Fazlullah to start an armed movement, which was later integrated into the Pakistani Taliban.

After the 2009 Pakistani military operation in the Swat Valley, Fazlullah fled to Afghanistan, where he quickly became a concern for U.S. intelligence officials and NATO commanders.

Pakistani intelligence officials have long been suspicious about the ability of Fazlullah and other Taliban leaders to remain in Afghanistan, and analysts said his selection as chief will exacerbate those concerns.

Last month, The Washington Post reported that Hakimullah Mehsud’s top deputy, Latif Mehsud, had been picked up by U.S. forces in Afghanistan on his way to a meeting with Afghan officials. The New York Times reported last week that Afghan intelligence officials had courted Latif Mehsud in an effort to fan the instability in Pakistan.

“There already was this fear, and now, with Fazlullah becoming the chief, Pakistan will become more alert, more cautious and more aware,” said Hasan Askari Rizvi, a Lahore-based military analyst and columnist, adding that the selection may even “cross a red line.”

In the Swat Valley, there was also concern Thursday that Fazlullah might soon be back, now that he has become Taliban chief.

“He is known as one of the most cruel militants,” said Zubair Torwali, executive director of the Institute for Education and Development in the Swat Valley. “And he knows all the commoners, so they are afraid he might return, with his guns.”