Australian diplomats in Kabul are in lockdown after a massive car bomb exploded near the German embassy.
Early reports indicate up to 50 people have been killed or injured.
Department of Foreign Affairs and Trade secretary Frances Adamson was giving evidence at a Senate estimates hearing in Canberra when she received the news.
She rushed out of the hearing to make phone calls.
Ms Adamson later reported that everything was alright at the Australian embassy but it was difficult to get information on the ground.
All Australian staff are safe and accounted for, she said.
The explosion has sent clouds of black smoke spiralling over the centre of the city in an area near the presidential palace and foreign embassies.
Houses hundreds of metres away from the blast on Wednesday were damaged, with windows and doors blown off their hinges.