Afghan men salvage their belongings at their shops following a suicide attack in Kabul, Afghanistan. Picture: Rahmat Gul/AP

Kabul - At least 56 people have been killed in a bloody 24 hours across three Afghan provinces. 

Three explosions in Kabul city, the capital of war-torn Afghanistan, left at least 11 dead on Thursday morning, including five women and one child, the Afghan Ministry of Interior said in a statement. 

Forty-five others were injured in the explosions, the ministry said. 

The explosions took place in eastern Kabul. The first involved a suicide bomber on a motorcycle who blew himself up next to a Ministry of Mines bus, Ministry spokesman Nasrat Rahimi said. 

The second explosion, triggered by an embedded home-made bomb, occurred in the same area, while a third explosion triggered by a car bomb took place further east, Rahimi said.

The Afghan Ministry of Mines confirmed that eight of its staff members were among the dead.

The Taliban claimed responsibility for the car bombing. Spokesman Zabihullah Mujahid claimed that a convoy of "foreign invaders" passing the area was targeted in the bombing. 

No group has yet claimed responsibility for the other attacks.

In the meantime, the Croatian Defence Ministry confirmed that two  Croatian soldiers wounded in a Taliban attack on Wednesday were in a stable condition. 

The ministry had said on Wednesday that a 27-year-old soldier had died due to wounds sustained from the bombing in the US military hospital in Bagram airfield. 

The soldier was an advisor for the Afghan security forces, according to the Croatian Defence Ministry.

Located some 50 kilometres north of Kabul city, Bagram airfield is the largest US military base in Afghanistan. 

This is the 14th such attack in Kabul city alone since the beginning of the year, leaving at least 79 dead and 537 others injured. 

Meanwhile, nine civilians - six women and three children - have been killed in a roadside bombing in the eastern Afghan province of Nangarhar, the provincial governor's office said.

Four others - one woman, two children and a driver - were injured in Thursday's incident, which took place in Khogyani district. 

The roadside bomb struck a minibus carrying a family that was heading to a wedding, according to a statement from the governor's office. 

The Afghan Presidential Palace condemned the attacks.

According to a quarterly report by the United Nations Assistance Mission in Afghanistan (UNAMA), explosives such as roadside bombs killed 53 civilians and left 269 others injured in the first three months of this year, a 21-per-cent increase on the same period last year. The figures do not include casualties from suicide bombings.

UNAMA said it is "very concerned" by the increase in civilian casualties from the use of home-made bombs.

The bombs are laid by militants to hamper the movement and progress of Afghan forces, but they frequently harm civilians.

At the same time, at least 35 policemen were killed in a Taliban attack on facilities in Afghanistan's northern province of Takhar, an official says.

At least 12 people, including six policemen, were also injured in the five-hour-long battle that took place on Wednesday night in Ishkamish district, former district governor Sayed Mehrabuddin told dpa.

He said Taliban fighters attacked three checkpoints and a military base used by police forces. 

However another official, provincial council member Mawlawi Keramatullah, said that the death toll was as high as 43 policemen with nine others missing. He said Taliban fighters overran the base and destroyed it before leaving. 

Despite ongoing talks between the US and the Islamist insurgents to find a political solution to Afghanistan's long-running conflict, both sides have ramped up attacks.

Parties to the conflict believe that their own bargaining position can be strengthened by increased military pressure.

The International Crisis Group, a think tank, recently warned in an analysis that escalating violence risks hardening positions in the talks. 

Following the attacks in recent weeks, Afghans on social media have also called for the talks to be suspended.