At least 28 people have been killed and 329 injured in a huge explosion in the centre of the Afghan capital Kabul, police and officials say.
A suicide attacker detonated a vehicle and a fierce gun battle followed. Officials say the attack is now over and the area has been cleared.
A Taliban spokesman said the group carried out the attack.
It comes a week after it said it was launching its “spring offensive”, warning of large-scale attacks.
Tuesday’s bombing happened during the morning rush hour in Pul-e-Mahmud, a busy neighbourhood where homes, mosques, schools and businesses nestle close to the Ministry of Defence, other ministries and military compounds.
Soldiers and security officers are reported to be among the casualties, but the majority are civilians.
The blast shattered windows up to 1.6km (one mile) away. The Associated Press quoted a police officer as saying it was one of the most powerful explosions he had ever heard, and he could not see or hear anything for 20 minutes after.
It appears the initial blast cleared the way for Taliban fighters to enter the area – a commonly used tactic.
“One of the suicide attackers blew up an explosives-laden truck in a public parking lot next to a government building,” Kabul police chief Abdul Rahman Rahimi told AFP news agency.
“The second attacker engaged security forces in a gun battle before being gunned down,” he added.
Hours after the assault was declared over, another blast rocked Kabul.