Taliban leader Mullah Omar died in a Karachi hospital
in 2013, Afghan security officials have insisted, despite the group's spokesman
telling Sky News he is "alive and leading the movement".
The one-eyed head of the hardline Islamist movement has not been seen in
public since 2001, and rumours that he was dead were reported in Pakistan and
Afghanistan this week.
The White House has called the reports "credible".
Sky sources said Omar's son, Mullah Yaqoob, had admitted his father
died some time ago, and a senior Afghan Taliban commander based in
Pakistan told Reuters Omar had died of natural causes, although he
did not specify when.
Some of the reports suggested his son had taken over.
Taliban spokesman Qariy Yousef Ahmadi told Sky News that the rumours
were not true.
"According to my information Mullah Omar is still alive and leading
the movement," he said.
But an Afghan official, speaking on Wednesday, said the reports were
correct and Omar had died in a hospital in Karachi, Pakistan, in April
2013.
Abdul Hassib Seddiqi, spokesman for Afghanistan's National
Directorate of Security, said: "He was very sick in a Karachi hospital and
died suspiciously there.
"We confirm officially that he is dead."
The militant group ruled Afghanistan in the late 1990s until 2001, when
a US-led offensive forced them from power.
Since then the Taliban has been fighting an insurgency against the
Western-backed government, killing thousands of civilians and military
personnel.
The militants have made significant territorial gains in recent months,
spreading Afghan forces thinly after the end of the US and NATO combat mission
at the end of last year.
Tentative peace talks aimed at ending the conflict have begun, although
the Taliban is split between those who back dialogue and those who want to
continue fighting.
A Pakistani security official, speaking anonymously because he is not
authorised to brief journalists, called the reports of Omar's death
"speculation" designed to disrupt the talks.
The next round of talks between the Afghan government and
Taliban representatives is due to be held in Pakistan on Friday.
Omar's death could complicate the peace process because it removes a
figurehead for the Taliban.
"Whether he is dead or alive is important because he is the
collective figure for the Taliban," said a Western diplomat with
connections to the Taliban leadership who spoke on condition of anonymity.
"If he is dead, it would be much more difficult to get negotiations
with the Taliban because there would be no collective figure to rally around
and take collective responsibility for entering peace talks."
But the presidential palace in Kabul, also officially confirming the
death, was optimistic about the talks.
"The government of Afghanistan believes that grounds for the Afghan
peace talks are more paved now than before, and thus calls on all armed
opposition groups to seize the opportunity and join the peace process," it
said.