Baqir Jabr al-Zubeidi, Iraq’s transport minister, said the number is likely to exceed 27 million by Thursday, al-Sumaria news reported.
The pilgrims who are from over 60 countries have converged on the Iraqi holy city of Karbala to hold mourning rituals marking Arbaeen.
Arbaeen, on which one of the largest religious gatherings in the world is held, is the 40th day after Ashura, the martyrdom anniversary of Imam, Imam Hussein (AS).
Last year, the number of pilgrims going to Karbala for Arbaeen reached 20 million.
Meanwhile, an Iraqi security source said the five terrorists who sought to carry out suicide attacks against Arbaeen pilgrims were identified and killed.
The source said that the terrorists were killed after an hour-long clash with security forces.