At least 28 people were killed when a bus carrying Shia pilgrims from Pakistan to Iraq crashed in central Iran late Tuesday.

Another 23 people suffered injuries in the crash, 14 of them serious.

According to a statement by the Ministry of Foreign Affairs, Emigration, and Egyptian Expatriates, Cairo affirmed its solidarity with Pakistan and the families of the victims, wishing the injured a speedy recovery.

Pilgrims gather in Karbala, Iraq, in what’s regarded as the largest annual public gathering in the world. The event draws tens of millions of people each year.