Two bomb blasts aboard separate minibuses killed at least nine people on Thursday in Mazar-i-Sharif, police said, a week after a deadly explosion rocked a Shiite mosque in the northern Afghan city.

The number of violent public attacks has fallen since the Taliban returned to power last August, but the Sunni Islamic State group has continued to target Shiites, who they view as heretics.

Thursday's blasts occurred within minutes of each other in different districts of Mazar-i-Sharif as commuters were heading home to break their dawn to dusk Ramadan fast, Balkh provincial police spokesman Asif Waziri told AFP.

"The targets appear to be Shiite passengers," he said, adding 13 people were wounded in the blasts.

"The enemies of Afghanistan are creating tension and division among our people." 

No group has so far claimed the bombings.

The blasts came just days after a deadly bomb attack at a Shiite mosque in Mazar-i-Sharif killed at least 12 worshippers and wounded scores more.

A separate bomb attack at another mosque in the northern city of Kunduz last week targeted the minority Sufi community and killed at least 36 people at Friday prayers.

In another attack, also targeting Shiites, two bombs detonated at a school in Kabul, killing six students.

The jihadist IS claimed the mosque attack in Mazar-i-Sharif, but no group has so far tkaen responsibility for the bombing in Kunduz.

Shiite Afghans, who are mostly from the Hazara community, make up between 10 and 20 percent of Afghanistan's population of 38 million.

The regional branch of IS in Sunni-majority Afghanistan has repeatedly targeted Shiites and minorities such as Sufis, who follow a mystical branch of Islam.

IS is a Sunni Islamist group, like the Taliban, but the two are bitter rivals.

The biggest ideological difference is that the Taliban sought only an Afghanistan free of foreign forces, whereas IS wants an Islamic caliphate stretching from Turkey to Pakistan and beyond.

Taliban officials insist their forces have defeated IS, but analysts say the jihadist group is a key security challenge. 

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