KABUL, Afghanistan - 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.

Two Afghan government officials said Akhtar Mohammad Mansour was shot Tuesday near Quetta, in western Pakistan. Afghan officials believe Mansour was either gravely injured or died before he could reach a Pakistan hospital.

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

Pakistan's foreign ministry announced this week that Ghani and Sharif were expected to meet, along with representatives of the United States and China, to try to reach a consensus over 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, who had been one of Omar's deputies, as the new Taliban leader. That angered some other Taliban commanders, resulting in an ongoing power struggle within the group.

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

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

Another Afghan government official, who spoke on the condition of anonymity, said some Afghan intelligence officials believe Mansour died en route to the hospital. In interviews with Reuters news agency, two Taliban commanders confirmed that Mansour had been shot.

But a spokesman for the Afghan Taliban, Zabiullah Mujahid, accused Afghan intelligence officials of making up the story to cover for recent battlefield losses.