Video report by ITV News Correspondent Paul Davies
A bomb hidden in a sewage tanker has killed at least 90 people and wounded 460 after being detonated near foreign embassies in Kabul.
The death toll includes a BBC Afghan driver after the devastating blast hit commuters in the Afghan capital, damaging the German, French, Turkish and Chinese embassies.
The Afghan government said 90 people had been confirmed dead in the still-unclaimed early morning suicide attack, which comes during the first week of Ramadan.
BBC Afghan driver Mohammed Nazir died and four BBC journalists suffered non-life-threatening injuries, the corporation announced.
BBC World Service director Francesca Unsworth said Mr Nazir, who had worked for the BBC for four years, was driving his colleagues to their office at the time and described his death as a "devastating loss".
The blast came at the start of the holy month of Ramadan and witnesses said they saw crowds gathered around ambulances that carried the dead and wounded to hospitals, trying to identify bodies.
German Foreign Minister Sigmar Gabriel confirmed embassy staff were among those injured in the powerful explosion.
He said at least one Afghan security guard was killed in the 8.25am (3.55am GMT) attack in Zanbaq Square as he condemned the blast.
"It hit civilians and those who are in Afghanistan to work for a better future for the country with the people there.
"It's especially contemptible that these people were the target," he said.
The US State Department said 11 US citizens working as contractors were among the wounded, adding that none of their injuries were considered life-threatening.
A French minister said there were no reports of French staff being hurt.
No group has yet said it carried out the attack.
Clouds of black smoke could be seen rising above the city centre, close to the presidential palace and foreign embassies after the blast.
A police spokesperson said the intended target remained unclear.
"It was a car bomb near the German embassy, but there are several other important compounds and offices near there too," he said.
"It is hard to say what the exact target is."
The explosion was so strong it was described by witnesses as feeling "like an earthquake", shattering windows and blowing doors off their hinges in homes hundreds of metres away.
The front of a building facing the street where the blast took place was torn off in the explosion.
The NATO-led mission in Kabul said Afghan security forces prevented the tanker which the bomb was housed in, from entering the city's unofficial "Green Zone" where the embassies are.