Gunmen attacked a British security contractors' compound Kabul, killing at least 10 people, only hours after President Ashraf Ghani outlined plans for peace in Afghanistan.
The Taliban claimed responsibility for the attack in the Afghan capital, which started when a car bomb exploded outside a facility of the G4S security group on the main road leading out of the city towards eastern Afghanistan.
"A number of gunmen entered the G4S compound right after the car bomb," said Najib Danish, an Interior Ministry spokesman.
The insurgents' main spokesman Zabihullah Mujahid said the attack had caused heavy casualties and had been launched in retaliation for casualties caused by security forces in the southern provinces of Helmand and Kandahar.
G4S, one of the world's biggest security groups, is one of a number of foreign security contractors operating in Afghanistan and provides guards for the area around the British embassy.
An official from the public health ministry said at least 10 bodies and 19 wounded had been taken to city hospitals but with clearance operations still going on late into the night, there was no definitive casualty figure.
"There was a bang and right after that, all the windows and ceiling collapsed over the children. All of the doors were shattered," said Hafizullah, a father who had brought three children to a city hospital. The children were wounded in a house near the contractors' compound.
The attack on a well-protected site underlines how insecure Kabul remains despite efforts by the United States and the Afghan government to open peace talks with the Taliban to end more than 17 years of war.
"It is unfortunate and events like this bolster our resolve for peace," Afghan National Security Advisor Hamdullah Mohib told reporters at the sidelines of a UN-sponsored conference in Geneva where Mr Ghani repeated calls for peace with the Taliban.
Efforts to open talks with the insurgents have picked up following the appointment of US special peace envoy Zalmay Khalilzad earlier this year, but the violence that kills thousands every year has continued.
Three US service members were killed close to the central city of Ghazni on Tuesday and at least 30 Afghan civilians were killed in a US air strike overnight, officials and local residents said.
Last week, more than 50 people were killed in Kabul when a suicide bomber attacked a banquet hall where a meeting of religious leaders was taking place.
Earlier on Wednesday, three gunmen attacked the Kabul residence of former spy chief Amrullah Saleh but there was no indication of any connection with the GS4 attack.
Earlier, Mr Ghani, who faces a re-election battle next year, told a donors conference in Geneva of plans to appoint a team to seek a peace deal, which he said would take at least five years to implement.
However the Taliban, who have sent representatives to meetings with Khalilzad, have so far refused to deal directly with the Kabul government, which they consider an illegitimate foreign-appointed regime.
Security officials have warned that violence is likely to escalate alongside peace moves as the Taliban seek to strengthen their position before any formal negotiations.