At least nine people were killed in two bomb blasts aboard separate minibuses in Afghanistan’s Mazar-i-Sharif on Thursday, authorities said, a week after a devastating explosion rocked a Shiite mosque in the northern city.

Since the Taliban retook power in Afghanistan last August, the number of violent public attacks has decreased, but the Sunni Islamic State organization has continued to target Shiites, whom they regard as heretics.

In the last two weeks of Ramadan, a series of devastating bombs targeting members of minority populations have wracked the country, killing and injuring dozens of people.

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 responsibility for the bombings.

Images posted on social media showed one minibus engulfed in fire, while the other was mangled with Taliban fighters transporting victims from the vehicle to hospitals.

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

That explosion was followed a day later by a separate bomb attack at another mosque in the northern city of Kunduz targeting the minority Sufi community.

It killed at least 36 people during 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 taken responsibility for the bombing in Kunduz and at the Kabul school.

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 remains a key security challenge.

Several arrests have been made in connection with recent attacks, according to Afghan government spokesman Zabihullah Mujahid, who spoke to AFP earlier Thursday.

“These attacks targeted places that did not have enough security like mosques and a school, but now we have stepped up security in such places,” he said.