Speaking in a joint press conference with the Iraqi interior minister on Friday, Luay al-Yasiri said some 4.5 million pilgrims were in Najaf to attend the mourning events, al-Sumaria TV reported.
He added that all of the measures planned to ensure the security of the pilgrims were carried out successfully.
Iraqi Minister of Interior, Othman Al-Ghanm, said at the press conference that forces and personnel from the defense ministry and interior ministry took part in operations to guarantee the security.
He added that there was no security issue in the holy city during the mourning ceremonies.
Friday marked the 28th day of the lunar Hijri month of Safar, the demise anniversary of Prophet Muhammad (PBUH) and martyrdom anniversary of Imam Hassan (AS), the second Shia Imam.