A suicide bomber attacked a packed Shiite mosque in the Afghan capital Tuesday, killing at least 54 people as throngs of worshipers observed the religious holiday of Ashura. More than 100 people were injured.

A wounded man and a boy try to stand up after a suicide blast targeting a Shiite gathering in Kabul on Tuesday. (REUTERS)

Graphic video shared by Russia Television, a Kremlin-financed satellite channel, starts by showing worshipers whipping their bare backs, a hallmark of observance of the holiday of Ashura. Ashura is the peak of a 10-day mourning period for Imam Hussein, a grandson of the prophet Muhammad who was killed in battle in the 7th century. It is also one of the most important days in the Shia calender, another sign that the attack could indicate coming sectarian violence.

The footage then cuts to the moment of impact of the explosive, showing bodies strewn on the ground and then carried away:

Abdul Ali Ahmat, who was inside the shrine distributing glasses of milk to worshipers when the blast occurred, told the Post: “I saw women, children and men . . . It was a horrible, horrible situation.”

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