A roadside explosion in northern Afghanistan claimed at least seven lives.

According to local authorities, the most recent incident in the violent nation of Afghanistan left at least seven dead in a roadside blast.

Officials from the city of Mazar-i-Sharif reported that employees of a petroleum business who were on a bus were among those murdered in the 7am (03:00 GMT) blast on Tuesday.

According to a local authority, those killed aboard the bus in Mazar-i-Sharif were employees of a petroleum firm.

The bomb was put in a cart at the side of the road. Asif Waziri, a police officer with the Balkh police division in Mazar-i-Sharif, claimed that the bomb went off as the bus approached.

In the town of Hairatan, which is close to the Uzbek border and has rail and road connections to Central Asia, the northern Balkh province is home to one of the nation's major dry ports.

The attacker's identity was not immediately known, despite repeated Taliban government promises to restore security to Afghanistan after decades of conflict.

In August of last year, the United States-led foreign troops that had invaded the country and overthrown the Taliban administration in 2001 withdrew and the Taliban government seized control.

A blast at a school in Aybak, a city in Samangan province that borders Balkh province, resulted in at least 19 fatalities and 24 injuries last month.

In a sequence of bombings in Mazar-i-Sharif in May, at least nine people died, while two more died in a simultaneous attack at a mosque in Kabul, the country's capital.

The incident in Mazar-i-Sharif was claimed by ISIL (ISIS), the Taliban's major adversary in Afghanistan, but not the explosion in Kabul.

In October, a suicide bomber targeted a mosque inside the compound housing Afghanistan's interior ministry, killing four people.