Thousands of Shiite Muslims have rallied across various parts of Pakistan ahead of tomorrow’s religious event of Ashura, or “Day of Remembrance”.

The holiest day on the Shiite Muslim calendar is observed each year on the 10th day of Muharram, the first month of the Islamic year, to mourn the 7th century death of Imam Hussain, the grandson of Prophet Muhammad.

At Saturday’s rally in Islamabad, thousands of Shiite Muslims were seen beating their chests with their hands and flagellating themselves with knives attached to chains.

Authorities have stepped up security across the country following intelligence reports that militants could target Shiites this week.