A suicide bombing has killed at least 63 people and injured 151 others in the centre of Afghanistan's capital, Kabul, officials say.
Attackers drove an ambulance laden with explosives past a police checkpoint into a street that was only open to government workers.
It happened near the old interior ministry building and offices of the European Union and High Peace Council.
The Taliban have said they carried out the attack, the deadliest for months.
A week ago, Taliban militants killed 22 people in a luxury Kabul hotel.
Witnesses say the area - home to foreign embassies and the city's police headquarters - was crowded with people when the bomb exploded on Saturday at about 12:15 local time (08:45 GMT). Plumes of smoke were seen from around the city.
Officials said the death toll would probably continue to rise as casualties were brought to hospitals for medical attention.
It is the deadliest attack in Kabul in several months
The hotel attack prompted the United States to repeat its demand that Pakistan expel Taliban members who have found sanctuary on its soil, with particular reference to the Haqqani network. On Wednesday a U.S. drone slammed into Pakistani tribal territory that borders Afghanistan, killing two Haqqani commanders, said Pakistani officials, who deny providing organized camps for their safety. Pakistan says the Taliban cross the porous border that separates the countries along with the estimated 1.5 million Afghan refugees still living in Pakistan.
The recent attacks have infuriated Afghans, frustrated by the worsening security after 16 years of war. The Afghans have expressed their anger with neighbor Pakistan for harboring insurgents and with the U.S.-led coalition for its inability to suppress the insurgency. They also have blamed the deteriorating security situation on a deeply divided government embroiled in political feuding that has paralyzed Parliament.
After Saturday's attacks Pakistan issued a statement that condemned the bombing, saying, "No cause or ends justify acts of terrorism against innocent people."
Afghan security forces, whose competency has been uneven, have struggled to fight the Taliban since the U.S. and NATO formally ended their combat mission in 2014.
U.S. President Donald Trump has pursued a plan that involves sending thousands more troops to Afghanistan and envisions shifting away from a time-based approach to one that more explicitly links U.S. assistance to concrete results from the Afghan government. The Republican president's U.N. envoy, Nikki Haley, said after a recent visit to Afghanistan that his policy was working and that peace talks between the government and the Taliban are closer than ever before.