BAGHDAD, June 13 (Reuters) - The U.S. military said on Wednesday a fresh attack on the Samarra shrine might provoke another spike in sectarian violence in Iraq and declared it was keeping the situation under close scrutiny. "Based on the results of last year's attack, we are obviously watching it very carefully," said spokesman Lt Colonel Christopher Garver. He said the U.S. military had not yet made an independent assessment of the latest incident at the revered Shi'ite mosque in the city of Samarra. Shi'ite officials and a witness said militants had blown up the two minarets left standing after a 2006 bombing which destroyed the dome of the Golden Mosque. That attack triggered a wave of sectarian violence last year that has killed tens of thousands of people and pushed Iraq to the brink of civil war.
