Kabul — The new leader of Afghanistan's Taliban insurgency may have been badly wounded or killed during a dispute with a rival, complicating efforts to revive stalled peace talks between the increasingly fractured militant group and the Afghan government, officials said here Thursday.

Three Afghan government officials said Akhtar Mohammad Mansour was shot Tuesday near the western Pakistani city of Quetta. Afghan officials think Mansour was either gravely injured or died before he could reach a Pakistani hospital.

But the Taliban's official spokesman and Pakistani intelligence officials denied that Mansour was in Pakistan. They accused Afghanistan's government of fabricating the episode, perhaps to undermine a meeting between Afghan President Ashraf Ghani and Pakistani Prime Minister Nawaz Sharif next week in Islamabad.

Pakistan's Foreign Ministry announced this week that Ghani and Sharif are to meet, along with representatives of the United States and China, to seek a consensus on whether peace talks between the Taliban and Ghani's government can be restarted.

An initial round of talks collapsed in late July when news broke that the Taliban's supreme leader, Mohammad Omar, had been dead for several years.

Some Taliban leaders then met to appoint Mansour, one of Omar's deputies, as the new Taliban leader. That angered some other Taliban commanders, resulting in a power struggle within the group.

If Mansour is dead or seriously wounded, that would be yet another blow to the peace process. Mansour is believed to have past ties to elements in Pakistan's intelligence service, and he has generally been viewed as more receptive to peace talks than some other Taliban commanders.

Sultan Faizi, a spokesman for Afghan Vice President Abdurrashid Dostum, said Mansour was shot Tuesday night while meeting with Taliban commander Abdullah Sarhadi. Sarhadi had been detained in Guantanamo Bay but was released in 2012.

Sarhadi may have been trying to mediate a dispute between Mansour and other Taliban leaders when the two sides began shooting at each other, Faizi said.

"Sarhadi and a group of other Taliban were killed," Faizi said. "Mansour was rushed to a hospital because of his severe wounds."

Another Afghan government official, who spoke on the condition of anonymity, said some Afghan intelligence officials think Mansour died on the way to the hospital.

Afghanistan's chief executive, Abdullah Abdullah, said through his spokesman that Mansour had been wounded in the encounter. Javed Faisal, the spokesman, said it was premature to speculate on whether the violent episode would harm the peace process.

In interviews with the Reuters news agency, two Taliban commanders said Mansour had been shot. One commander told Reuters that Mansour was shot four times with an AK-47 assault rifle.

But a spokesman for the Afghan Taliban denied the reports. Zabiullah Mujahid said Afghan intelligence officials had made up the story to cover battlefield losses.

"The enemy merely wants to draw attention away from their failures," Mujahid said. "We request all independent and unbiased media outlets to stop damaging their reputations with the publication of such unfounded reports."

Several Pakistani intelligence officials also denied that Mansour was shot. "I would call it a conspiracy by the jackals acting behind the scene to sabotage relations between Pakistan and Afghanistan," said one official, who spoke on condition of anonymity.

Agence France-Presse, however, quoted another anonymous Pakistani intelligence official as saying Mansour was "very seriously injured" in the clash.

Local officials in Quetta, where much of the Taliban leadership has lived since the group was driven from power in Afghanistan in 2001, were skeptical.

"This is not a small news that one can hide," said one government official in Quetta, who spoke on the condition of anonymity so he could freely express his views on the matter. "If any firing incident did take place, everyone would have known."

The U.S.-led coalition in Afghanistan had no immediate comment on the allegations.

Details on the whereabouts of Afghan Taliban leaders have proved especially difficult for Western officials to pin down. For years, there were off-and-on rumors that Omar was dead. But even U.S. intelligence officials were surprised when the Taliban confirmed in July that Omar died about two years earlier.

After Mansour was named Omar's successor, another key Taliban leader, Mullah Rasool, announced a rival leadership group that was challenging Mansour's rule.

Last month, Rasool's deputy, Mansour Dadullah, was reportedly killed when fighting broke out between the two Taliban factions in Afghanistan's southern Zabul province.