(Adds Taliban confirmation of Mullah Omar's death)
* Fighting in Helmand a reminder of danger Taliban poses
* Afghan government seeking to negotiate peace
* Latest round of talks postponed
* Afghan Taliban name leader to succeed Mullah Omar
By Jibran Ahmad
PESHAWAR, Pakistan, July 30 (Reuters) - The Taliban have chosen late supreme leader Mullah Omar's longtime deputy to replace him, two militant commanders said on Thursday, as Pakistan announced that peace talks between the insurgents and the Afghan government had been postponed.
Pakistan cited reports of Omar's death as the reason for the delay in negotiations, amid fears they could trigger a potentially bloody succession battle and further deepen divisions within the militant movement.
Mullah Akhtar Mohammad Mansour was appointed leader at a meeting of the Taliban's top representatives, many of whom are based in the Pakistani city of Quetta, according to the sources who were present at the shura, or gathering.
"The shura held outside Quetta unanimously elected Mullah Mansour as the new emir of the Taliban," said one commander at the Wednesday night meeting.
"The shura will release a statement shortly."
Siraj Haqqani, leader of the powerful Haqqani militant faction, will be a deputy to Mansour, both commanders added.
Mansour will be only the second leader the Taliban have had, because Omar, an elusive figure rarely seen in public, founded the ultra-conservative Islamist movement in the 1990s.
The Taliban eventually conquered most of Afghanistan, imposing strict Islamic law before being driven from power in 2001 by a U.S.-led military intervention.
"There has always been Mullah Omar. So this is a completely new situation," said Bette Dam, author of an upcoming biography of the Taliban leader.
LEADER LONG RUMOURED DEAD
Taliban spokesman Zabihullah Mujahid on Thursday confirmed that Omar was dead, although his statement indicated he had died recently rather than over two years ago as the Afghan government had said on Wednesday.
"For some time, (Omar) has been suffering a kind of sickness and over the last two weeks it became more serious, and due to that illness he passed away," Mujahid said, calling on Taliban commanders to hold prayers for him.
The statement did not mention the succession.
Afghanistan had said Omar died in April, 2013 in a Pakistani hospital, but Pakistani officials could not confirm that.
"We are aware of the reports and trying to ascertain the details," Pakistani foreign ministry spokesman Qazi Khalilullah said.
The Taliban statement, for its part, said Omar had never left Afghanistan in the last 14 years.
Omar had not been seen in public since 2001, and rumours of his death had proliferated in recent years. Insiders say Mansour has long been running the Quetta shura, prompting many disgruntled commanders to demand he produce Omar.
TALIBAN DIVISIONS OVER TALKS
The announcement of Omar's death threw into disarray a fledgling peace process fostered by neighbouring Pakistan aimed at ending more than 13 years of war between the Taliban and the Western-backed government in Kabul.
Mujahid said earlier on Thursday that the Taliban's official team of negotiators based in Doha was "not aware of this process" in Pakistan.
Later in the day, the Pakistani foreign office said a planned second round of meetings set for Friday would be delayed at the request of the Taliban leadership. The two sides held inaugural talks in Pakistan earlier this month.
"Pakistan and other friendly countries of Afghanistan hope that the Taliban leadership will stay engaged in the process of peace talks in order to promote a lasting peace in Afghanistan," the foreign ministry statement said.
Mansour's appointment is unlikely to please everyone in the Taliban. Key field commanders have criticised the peace process and vowed to fight for power, rather than negotiate it.
Several have left the movement altogether, pledging allegiance to Islamic State in the Middle East and targeting the Taliban itself in a worrying new development.
FIGHTING GOES ON
In a reminder of the threat posed by insurgents stepping up their campaign to overthrow the government, the Taliban captured a district in the southern province of Helmand that foreign troops struggled to secure for years.
District officials said the Taliban had wrested control of the Now Zad district on Wednesday after two days of fighting.
Residents of the area, speaking to Reuters by telephone, said bodies of security personnel and Taliban fighters were lying in the streets after the battle.
The Taliban has taken control of pockets of territory across the country since NATO withdrew most of its forces at the end of 2014, leaving the Afghan army and police to quell the violence. Thousands of people are killed each year. (Additional reporting by Jessica Donati in Kabul and Katharine Houreld in Islamabad; Writing by Kay Johnson; Editing by Mike Collett-White)
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