The younger half-brother of Afghan President Hamid Karzai, one of the most powerful and controversial men in southern Afghanistan, was shot dead at his home on Tuesday by a senior and highly trusted family security guard.
Ahmad Wali Karzai's assassination will leave a dangerous power vacuum in volatile Kandahar province, the Taliban's birthplace and a focus of recent efforts by a surge of US troops to turn the tide against the insurgency.
He was accused of corruption and ties to the opium trade, but always denied any wrongdoing and was strongly supported by his brother whose influence he shored up in the south.
President Karzai may find his reach there is now limited as a potentially violent power struggle plays out among the possible successors to his brother.
"We felt more safe when Ahmad Wali Karzai was around," said Tooryalai Wesa, the governor of Kandahar who outranked Karzai, but like almost everyone in the province deferred to him.
"His loss will have a negative impact on issues with tribes, and current affairs and security. Kandahar today witnessed the darkest day," Wesa added at a news conference.
Ahmad Wali Karzai was head of the Kandahar Provincial Council, a largely consultative role, but his power came from his family and tribal connections and his fortune.
Born in 1961, he was shot dead by Sardar Mohammad, a senior member of the Karzai family's security team in Kandahar who had known his victim for at least a decade and was based at a compound in the village of Karz, where both brothers were born.
He travelled into Kandahar on Tuesday morning saying he had an application he needed to give his boss, Kandahar police chief Abdul Razeq told a news conference.
"The man carried his pistol through the security checks to Wali Karzai's room. As soon as Wali Karzai came out of bathroom, he opened fire and shot him in the head and chest," Razeq said.
Mohammad was shot dead by Karzai's bodyguards moments after opening fire, witnesses and officials said.
Ahmad Wali Karzai was the first of Karzai's close relatives to be killed since he became president, but their father was assassinated in 1999 while in exile in Pakistan.
"My younger brother was martyred in his house today," President Karzai said at a news conference in Kabul held with his visiting French counterpart, Nicolas Sarkozy. "I hope these miseries which every Afghan family faces will one day end."
Karzai was travelling down to Kandahar for the burial, set for early Wednesday morning so his siblings had time to arrive. Security was dramatically tightened, with helicopters circling overhead, extra checkpoints and many roads closed.
The killing cast a shadow over the city, which has been a focus of violence in recent months as the Taliban came under pressure in surrounding districts from a wave of extra troops ordered in by US President Barack Obama in 2009.
More than half of all assassinations in Afghanistan since March were carried out in Kandahar city, a UN report said.
The Taliban claimed responsibility for one of the most high-profile political killings of the last decade after news of his death became public. In the past the security services have sometimes doubted instances when they have claimed responsibility.
Years in power and his sometimes ruthless operating methods meant there might be many other people keen to target Karzai, who was often known simply by his initials, AWK.
"I'm not sure whether I would assume that this was the Taliban because he had a lot of enemies down there," said Thomas Ruttig, co-director of the Afghanistan Analysts Network.
But regardless of whether they had a hand in the killing, the Taliban are likely to benefit from his death.
"(He) is irreplaceable in Kandahar," said Haroun Mir, head of Afghanistan's Center for Research and Policy studies.
"Despite all the criticism, he was a stabilising factor in Kandahar. Now Ahmad Wali Karzai is not there, others in Kandahar will be afraid. This is a real boost to the Taliban."
Ahmad Wali Karzai had survived several other assassination attempts, including in May 2009 an ambush on the road to Kabul when Taliban insurgents killed one of his bodyguards.
CRITICAL POWER BROKER
Ahmad Wali Karzai returned to Afghanistan after the removal of the Taliban government, leaving behind a career as a restaurateur in Chicago to eventually become probably the most powerful man in Kandahar.
The president will miss his support, particularly at a time when he is mired in a long-running dispute with parliament and faces a slow but steady reduction in Western financial and military support over the next four years.
The killing is also likely to alarm Western military and civilian officials, despite misgivings they had about him, because it comes at a time when they are trying to map out their departure from Afghanistan.
"The Americans and the British were extremely dependent on him for keeping a lot of these very prominent Pashtun tribes in line and not going over to the Taliban," said Ahmed Rashid, an expert on the Taliban and longtime friend of the Karzai family.