Governor Aqil Khazali said only one missile struck Karbala; the other two hit the desert. No one was injured.
Thousands of police have been deployed in and around Karbala for fear of possible sectarian violence during the pilgrimage marking the 40th and final day of mourning for Imam Hussein, the Prophet Muhammad's grandson. The commemoration will take place on March 20.
Two years ago, coordinated attacks left 181 people killed in Karbala.