Kandahar - A suicide truck bomb in southern Afghanistan on Tuesday killed two civilians and wounded more than 40, officials said, in the latest attack since the Taliban began their annual offensive.
The attacker detonated a lorry loaded with explosives at the gate of the police headquarters in Lashkar Gah, the capital of volatile Helmand province.
Afghan troops and police are battling the Taliban in the first "fighting season" since NATO ended its combat mission and left local forces to take charge of security.
The Helmand blast came less than two days after 11 soldiers were killed in a Taliban ambush in the normally relatively peaceful western province of Herat.
"It was a suicide truck bomber detonating his vehicle at the gate of police headquarters," provincial police spokesman Farid Ahmad Obaid told AFP.
"Our initial reports show 40 wounded, two killed," he said, adding that all of the casualties were civilians.
Provincial spokesman Omar Zhwak confirmed the attack.
"The blast was very powerful. Most of the wounded people are civilians who were hit by broken glass inside their homes," he told AFP.
Also read: Taliban ambush kills 11 Afghan soldiers
A doctor at the emergency hospital in Lashkar Gah said 40 civilians were brought to the hospital.
There was no immediate claim of responsibility for the attack. But the Taliban, who launched their annual spring-summer offensive in late April, vowed nationwide attacks in what is expected to be the bloodiest summer for a decade.
After the Helmand attack a small blast hit a military vehicle in Kabul, police said, though there were no casualties.
"A small sticky bomb attached to a military vehicle detonated in western Kabul this morning. Only the car was damaged," Kabul police spokesman Ebadullah Karimi Kabul told AFP.
NATO's combat mission formally ended in December after 13 years, but a small follow-up foreign force named Resolute Support has stayed on to train and support local security forces.
Stretched on multiple fronts and facing record casualties, Afghan forces are struggling to rein in the militants even as the government makes repeated efforts to jump-start peace negotiations.
The Taliban's annual summer offensive has sent civilian and military casualties soaring and threatened major cities for the first time in a decade.
A fierce battle has been going on in the northern province of Kunduz, where last week Afghan forces recaptured a key district from Taliban fighters who had threatened to overrun their first provincial capital since being toppled from power in 2001.
Last week also saw the militants launch a brazen assault on parliament in Kabul, detonating a car bomb at the entrance and trading fire with security forces.
Police and soldiers beat back the attack with only two civilians killed, but the incident highlighted the Taliban's continuing ability to strike even at the heart of the heavily-secured capital.