KARBALA, Iraq (CNN) -- A female suicide bomber apparently targeting Shiite worshippers killed at least 40 people and wounded at least 65 in Karbala on Monday, according to an Interior Ministry official. Iraqi security forces gather around the site of a car bomb explosion in Baghdad on Monday. The incident occurred one-half mile from the Imam Hussein shrine of Karbala. Karbala is a Shiite holy city, and the Imam Hussein shrine is one of Shiite Islam's holiest locations. The shrine marks the burial spot of Hussein bin Ali, the grandson of the Prophet Mohammed, who was killed in battle nearby in 680.
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NEW: 2 U.S. soldiers killed by roadside bomb in Baghdad on Monday, U.S. says
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NEW: Other roadside bombs in Baghdad kill one police officer, injure four people
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Death toll rises to 40 in explosion in Karbala, official says; 65 injured
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Explosion was near holy shrine for Shiite Muslims, burial spot of Hussein bin Ali
No more information was immediately available about the blast southwest of the capital city, @placeholder.