The Pakistani Taliban, riven by infighting, splintered into two major groups Wednesday as the leader of its dominant faction announced that it was severing ties with chief Taliban commander Maulana Fazlullah.

During a rare news conference in Pakistan’s northwestern tribal areas, a spokesman for the Taliban’s Mehsud faction said it was breaking away because other elements of the Pakistani Taliban are too violent and undisciplined. The Mehsud faction, led by Khan Said, will now operate independently from its historical base in North and South Waziristan.

“The central leadership has gone into the hands of unseen forces, sectarian issues and extortion in the name of Taliban,” said Azam Tariq, a spokesman for Said, who also goes by the name Sajna. “We have decided to go our own way.”

The rift within the Pakistani Taliban — also known as Tehrik-e-Taliban Pakistan, or TTP — can be traced to a U.S. drone strike in November that killed the group’s leader, Hakimullah Mehsud. He had been implicated in a 2009 attack that killed seven Americans at a CIA outpost in eastern Afghanistan.

After he was killed, a power struggle erupted, resulting in the group’s main factions at times turning their weapons on each other. The formal split comes as Pakistan’s government struggles to negotiate a peace agreement with the Taliban. Said remains interested in continuing those talks, Tariq said, but had been stymied by other Taliban leaders, including Fazlullah.

Several analysts said the split is a significant setback for a militant group that has been waging a bloody insurgency against Pakistan’s government and has been linked to attacks on Western interests.

Mehran Ali Khan, a senior analyst at the Fata Research Center, said that the Mehsud faction has always been the dominant wing of the Pakistani Taliban and that its departure from the central organization “will weaken the Pakistani Taliban a lot.”

“Said was the most powerful commander of the TTP, so if they separate, the TTP will exist only on paper, and their influence and power will decrease,” said Khan, adding that Said also has the support of the “Punjabi Taliban” operating in eastern Pakistan.

But analysts are divided about whether the split will help or complicate Pakistan’s efforts to control the insurgency, which is blamed for about 50,000 deaths in the past decade.

Khan, whose organization monitors militant groups in the Swat Valley and Pakistan’s tribal areas, said the division within the Taliban could result in even more attacks in the short term as the rival groups seek to exert influence. Others said, however, that Said appears to be projecting himself as a less confrontational Taliban leader, which may limit the violence.

“This is a major blow to the Pakistani Taliban as it will lose its centrality,” said Rustam Shah Moh­mand, an Islamabad-based analyst who has been helping Prime Minister Nawaz Sharif in the negotiation process. “There is an opportunity for the government to immediately engage the Sajna group in meaningful peace dialogue.”

Pakistan’s military, however, is likely to ultimately decide how much space and time Sharif will have to reach a negotiated settlement.

After eight Pakistani soldiers were killed in a roadside bombing in North Waziristan near the Afghan border, the military launched two days of airstrikes last week that it said killed more than 60 suspected militants, including several commanders.

The insurgents responded by attacking an army post, killing four Pakistani soldiers. The next day, the army raided a town in North Waziristan that was once home to Afghan refugees but is now thought to harbor militants.

According to some accounts, up to 300 structures were demolished in the fighting.

In recent days, Afghan officials also have accused Pakistan’s army of launching artillery strikes across the border.

Afghanistan’s Tolo News reported Wednesday that 693 artillery shells had landed in the northeastern Afghan province of Konar since Saturday.

Gen. Habib Sayedkhili, the provincial police chief, was quoted as saying that several people had been killed and more than 130 families had fled their homes.

In a sign of the growing tension, several Afghan senators told Tolo News that they expect the Kabul government and the Afghan military to respond to the attacks.

A spokesman for the Pakistani military was unavailable to comment Wednesday.

The Pakistani Taliban claims to be independent of the Afghan Taliban. But the groups are thought to coordinate activities.

After Mehsud was killed in the drone strike, Pakistani Taliban leaders selected Fazlullah as his replacement. Fazlullah, thought to live in Afghanistan, is reputed to be a hard-line commander and in 2012 ordered the killing of Pakistani schoolgirl Malala Yousafzai. Yousafzai, who was 15 at the time, was shot in the head on her school bus but survived and was a nominee for the 2013 Nobel Peace Prize.

Fazlullah’s appointment as commander resulted in considerable friction with Said, leading to intra-Taliban clashes that killed as many as 80 people in the past six months, according to tribal elders.

A key source of the dispute centered on who would receive the money that Taliban commanders have been collecting through extortion from the southern port city of Karachi, according to one militant, who spoke on the condition of anonymity to discuss the matter freely.

“This opens up a great opportunity for Pakistan,” said Talat Masood, a retired general and military analyst, referring to the split. “We should use it to our advantage to try to bring peace.”

Shaiq Hussain contributed to this report.