A suicide bomb was detonated near the German Embassy in Kabul during rush hour Wednesday morning, killing 80 people close to a highly secure diplomatic area, Afghan officials said.
The attack took place near Zanbaq Square in the heavily fortified zone, with civilians said to be the main casualties. The morning rush-hour blast created a massive crater and blew out windows and doors hundreds of metres away.
The Taliban have denied carrying out the attack. There has been no word so far from so-called Islamic State.
The bomb went off at about 08:25 local time (03:55 GMT) during rush hour at the diplomatic quarter.
Casualty numbers are expected to rise.
Those operating in Kabul should confirm safety of all personnel.