Mohammad Hassani, an official in the road and transportation department of Ilam Province, said on Tuesday that the number of Iranian pilgrims crossing both in and out of Mehran border on Monday stands at 123,000.
The number of pilgrims leaving Iran for Iraq is increasing at Mehran border, he added.
Mehran border is located near Iran's western border with Iraq. It is one of the major borders for crossing cars, trucks and pilgrims to Iraq.
Arbaeen, which is one of the largest religious gatherings in the world, comes 40 days after Ashura, the martyrdom anniversary of Imam Hussein (PBUH).
Each year, millions of people flock to Karbala, where the holy shrine of Imam Hossein is located, to perform mourning rites.
This year, Arbaeen falls on Saturday, October 19.
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