At least four people were killed and 29 wounded on Wednesday in a suicide motorcycle blast in Kabul that was claimed by the Taliban, who said it targeted a minibus carrying Afghan spy agency employees.
The attacker detonated his explosives-laden vehicle in an area of the Afghan capital close to government ministries, parliament and the offices of foreign companies, officials and witnesses said.
"The number of casualties that police have taken to hospital is four martyred," interior ministry spokesman Zemarai Bashary told AFP.
Health ministry spokesman Ghulam Sakhi Nuroghli said that 29 wounded had been registered by a hospital close to the scene of the blast.
"And one of the wounded is in a critical condition," Nuroghli told AFP.
Witnesses reported seeing fragments of a motorcycle and human body parts likely to be from a suicide attacker, while an AFP photographer saw pools of blood on the road and the shattered windows of several vehicles nearby.
"I heard a huge explosion which broke all the windows and rushed out of the house. I saw thick smoke and dust and a minibus, a pick-up truck and a civilian car were damaged," witness Ahmad Waseem told AFP.
"There were three people wounded lying on the ground. There were parts of a blown-up motorcycle and blown-up body parts of the suicide attacker... the explosion was so heavy that it shattered windows several streets away," he said.
The blast took place in front of a psychiatric hospital and close to a mosque just after 8.00am (0330 GMT).
A spokesman for the Taliban, Zabihullah Mujahid, claimed responsibility for the attack and said it had been carried out by a Taliban suicide bomber against employees of the National Directorate of Security (NDS) travelling to work.
Mujahid claimed the bomb killed 17 people and wounded another 14.
An NDS official at the scene also said the minibus hit in the blast was carrying its employees.
Afghan President Hamid Karzai condemned the attack "in the strongest possible terms" and said the perpetrators had achieved nothing but the killing of innocent civilians.
"Carrying out suicide attacks in places where hundreds of civilians, women and children commute, is a barbaric, inhumane and un-Islamic act and can only be carried out by those who are foreign mercenaries," he said.
A second blast in the east of the country killed an NDS official and his two bodyguards, and wounded another two people, a provincial medical official said.
A roadside bomb struck the vehicle of one of the deputy directors of NDS for eastern Kunar province while he was travelling to work in the outskirts of the provincial capital, Assadabad.
"Three dead bodies including a NDS deputy operations chief of Kunar and two of his bodyguards were brought to our hospital as well as two wounded," Assadullah Fazli, the provincial health director, told AFP.
The last bomb blast in Kabul occurred on January 4 when a policeman was killed and three civilians were wounded as the officer tried to defuse a homemade device.
The last major attack in the Afghan capital came last month, when two suicide bombers targeted an Afghan army bus, killing five military personnel.
There are about 140,000 international troops in Afghanistan fighting Taliban militants.