Unity plea wiped out in huge blast
The Imam Ali mosque in Najaf is revered by the world's 120 million Shiite Muslims and has been a place of pilgrimage for centuries.
Historians say the gold-domed mosque of Imam Ali bin Abi Talib named after the murdered cousin and son-in-law of Islam's prophet Muhammad was built in 977 in Najaf, a city regarded by Shiite Muslims as the faith's third holiest in the world after Mecca and Medina in Saudi Arabia.