An explosion killed at least 55 people in a shrine at the heart of Afghan capital Kabul, followed by a bicycle-bomb that went off killing four more people outside a mosque in the northern city of Mazar-i-Sharif on Tuesday. The attacks come the day after Western governments pledged long-term support to Afghanistan after combat troops leave in 2014. By targeting commemorations of the Ashura festival, the largest event in the Shiites’ religious calendar, the attacks could mean the resurgence of a historically violent relationship between Sunnis and Shiites in Afghanistan. Large sectarian attacks have plagued neighbouring Pakistan for decades, but have not taken in place in Afghanistan since the fall of the Taliban in 2001. No one has claimed responsibility for the attacks.