Battle of Kerbala

Ashura commemorates the death of Prophet Mohammad's grandson Hussein at the battle of Kerbala in 680 and defines Shiism and its rift with Sunni Islam.

Battle of Kerbala, in which Muhammad's grandson, Imam Hussain, was killed in battle along with his followers.

Cockburn initially lays out how the recurring themes of martyrdom and oppression in the Shi'a faith can be traced back to the death of Imam Hussein at the battle of Kerbala in 680AD.

Thousands chanted "Haider, Haider" another name for Imam Ali, Imam Hussein's father, to commemorate the slaying of his son in the seventh century battle of Kerbala. Groups of men, some riding horses, dressed up in medieval military outfits with helmets and chainmail to re-enact the battle between followers of Hussein and his enemy Yazid.

US commanderGeneral Tommy Franks confirmed one of the Apaches involved in the battle of Kerbala had failed to return.

Sunday's attack occurred just days before Ashura, the Shiite religious commemoration of the slaying of Prophet Mohammad's grandson Hussein at the battle of Kerbala in 680 AD.