One of the darkest moments in the modern history of the Arab world happened more than four decades ago, when then-Syrian President Hafez Assad launched what came to be known as the Hama Massacre. From 10,

A senior commander told NBC News that tanks had been used during the incursion and that rebels had freed hundreds of prisoners.

Capturing Hama would leave just one major city, Homs, in government hands on the road from rebel-held northern Syria to Damascus.