The Afghanistan government has said it is investigating reports that the leader of the Taliban, Mullah Mohammad Omar is dead.
In a press conference in Kabul, a Government spokesman said: "We are still in the process of assessing those reports."
The announcement followed reports in Afghan local media that Omar, who has not been since 2001, was dead but have died as long as two years ago. Some of the reports also indicated Mullah Omar's son was in a position to take over the Islamist insurgency that is fighting against Afghanistan's foreign-backed government.
Omar went into hiding 14 years ago after his government was forced from power by the US-led Coalition following the 911 attacks in the USA.
The Taliban has yet to comment on the claims.
The Afghan intelligence agency confirmed a third top Islamic State commander was killed in a drone strike in eastern Afghanistan this week.
Shahidullah Shahid, a former member of the Pakistani Taliban who defected to the Islamic State and was operating in Afghanistan, was killed along with five militants, an official said.
An increasing number of militants are pledging allegiance to the Islamic State in Afghanistan, making them a target of deadly strikes there by the U.S. unmanned aircraft.
An explosion has taken place in the tightly-guarded diplomatic quarter of Afghan capital, Kabul, today.
No further details of the explosion were immediately available.
A loud explosion followed by gunfire has been heard outside the Afghan parliament in Kabul, witnesses have said.
Social media reports suggested the parliament was "under siege" and that multiple explosions had been heard.
Police confirmed that four bombs had been set off outside the parliament building and that the Taliban had claimed responsibility.
Television footage showed politicians being evacuated from the building during the attack, while pictures posted to Twitter showed smoke rising near the area.
It is not immediately clear whether there are any casualties.
The Taliban have 'killed 20 police officers' in Southern Afghanistan, The Associated Press is reporting.
BREAKING: Official: Taliban kill 20 police officers as they overrun checkpoints in southern Afghanistan
Prince Harry was among British dignitaries who attended the dedication of a memorial to the 453 British soldiers who died in Afghanistan.
The ceremony took place at the National Memorial Arboretum near Lichfield in Staffordshire on Thursday.
The memorial is a reconstruction of one at the UK's Camp Bastion in Afghanistan's Helmand province, left behind when British soldiers pulled out in 2014.
Prince Harry served in Afghanistan, lending a poignancy to his speech as part of the ceremony.
ITV News' Correspondent Dan Rivers reports:
Prince Harry paid tribute to British service personnel killed on combat operations in Afghanistan, as he unveiled a memorial to their sacrifice at the National Memorial Arboretum.
Speaking at a service of dedication to unveil the Bastion Memorial, which is inscribed with the 453 names of those killed, he said they will "forever be in our hearts".
"As we sit here amongst friends, we can take comfort in the knowledge that they gave their lives doing a job they loved, for a country they loved, and amongst mates who loved them dearly."
He added: "Once this ceremony is ended and all the trappings of the day have been cleared away, this will become a place of pilgrimage, a quiet space for remembrance just as it was in Camp Bastion, all those miles away."
The British man killed in a terrorist car bomb attack in Afghanistan has been named by government officials as Michael Hampshire, from Huddersfield.
Mr Hampshire was working as a security contractor for the close protection team of the EU Police Mission in Kabul when he was killed.
In a statement released through the Foreign Office, Mr Hampshire's family said he was a "loving fiancé, son, grandson, brother, uncle, cousin and a friend to everyone who knew him".
No words can explain what we are going through at this time and we will miss Michael dearly.
We would like to take this opportunity to thank people for the messages we have received but would now like, as a family, to grieve for Michael in peace.
Known as Mic, Mr Hampshire leaves behind a fiancée of more than six months, Claire Taylor.
The attack appears to have deliberately targeted vehicles belonging to the EU police training mission. The Taliban has claimed responsibility.
Foreign Secretary Philip Hammond has condemned the "cowardly" attack that has killed at least three people, including a Briton, and wounding 18.
He said: "This is the second attack in a matter of days for which the Taliban have claimed responsibility and I strongly condemn their cowardly actions.
"I can confirm that a British security contractor is among those killed in the attack. His family has been informed and my thoughts are with them at this incredibly difficult time. Consular staff stand ready to provide support.
"Two Afghan women have also sadly lost their lives and many more have been injured. These attacks must not stop the people of Afghanistan, with the support of the international community, working towards a more peaceful future."
A Foreign Office has confirmed that a British national has been killed in a terror attack in the Afghan capital of Kabul.
A Taliban suicide bomber detonated an explosives-packed car near the international airport in the capital, Kabul, killing at least three people and wounding 18.
A spokesperson said: "We can confirm that a British national was tragically killed in a terrorist attack in Kabul this morning. We stand ready to provide consular assistance to the family."
The attack this morning appears to have targeted vehicles of the European Union police training mission. The car bomb was detonated near the office of the Afghan Civil Aviation Authority, which is a few hundred metres from the airport terminal. A Taliban spokesman claimed responsibility for the attack.