Over a dozen people have been killed in a series of explosions in Afghanistan’s capital Kabul and the country’s northern city of Mazar-i-Sharif, according to reports.

“The bombs were placed on board three minibuses in different neighborhoods of the city,” Balj provincial police spokesman Asif Waziri told AFP, adding that 15 people were injured.

Another explosion also occurred near the Hazrat Zakaria mosque at a traffic junction in Kabul city. Authorities said the targets were vehicles, but had injured citizens nearby.

According to AFP, a hospital source said all of the victims were civilians, including women and children, adding, “we are still admitting wounded people to the hospital and trying to save their lives.”

The incident follows another explosion on 24 May in a mostly Shia neighborhood in Kabul, where at least two people were killed and four injured, officials confirmed.

Kabul Police spokesman Jalid Zadran said that the explosion was caused by a gas canister, and that an investigation has been opened into the incident.

“Firefighters and security forces arrived on the scene and extinguished the fire; the incident took place in a store in the Naqash neighborhood in western Kabul,” Zadran said.

A resident quoted by German news agency DPA said the area was cordoned off by the Taliban and noted that several homes have suffered material damage.

Shia-majority neighborhoods in western Kabul have been the scene of several attacks in recent months.

According to the Interior Ministry, another bombing hit a mosque in Kabul, killing at least two people and wounding 10 others.

No group has so far claimed responsibility for the four bombings in the West Asian country.

The number of bombings has declined in the country since the Taliban seized power last August, but a series of bomb attacks, killing at least 10 people and wounding 20 others, hit the country in late April during the holy month of Ramadan.