Gunmen set off at least three explosions in the Afghan capital, Kabul, on Wednesday and then battled the security forces from buildings they occupied in the latest in a spate of violence to rock the city.At least six people were wounded, said health ministry spokesman Wahidullah Majroh, adding the casualty toll was likely to rise.
Afghanistan's Western-backed government is fighting an intensifying war with both the Taliban and the Islamic State that has turned much of Kabul into a high security zone of concrete blast walls and razor wire.
The first blast was near a police station in western Kabul's Dasht-e-Barchi district, at around midday, said police spokesman Hashmat Stanekzai.
Minutes later, two back-to-back explosions went off in the central Shar-e-Naw commercial district.
Najib Danish, spokesman for interior ministry, said police were battling an unknown number of gunmen in both Dasht-e-Barchi and Shar-e-Naw.
"A number of gunmen at both sites under attack are engaged with the security forces," Danish said.
"At both sites the insurgents took positions in nearby buildings."
There was been no claim of responsibility.
Noor Mohammad a security guard at a private bank at Shar-e-Naw, said one blast went off near the office of a travel agency that processes visa applications for India.
A senior official at the Indian embassy confirmed that one blast took place outside a travel company's office and many security guards were injured.
The Afghan capital has seen an increase in bombings and other attacks against the security forces and civilians since the Taliban announced the beginning of their spring offensive on April 25.
Fighting traditionally picks up in Afghanistan as warmer weather melts snow in mountain passes, allowing insurgents to move around more easily.
Twin blasts in Kabul on April 30 that killed 26 people including nine journalists.