The Latest: Syrian troops backed by Russian airstrikes launch ground offensive

A Russian warship passes through the Bosphorus, in Istanbul, en route to the Mediterranean Sea, Tuesday, Oct. 6, 2015. Russia began launching military operations in Syria on Wednesday, targeting mainly central and northwestern Syria, strategic regions that are the gateway to its long-term ally President Bashar Assad's main strongholds. (AP Photo) (The Associated Press)

Map shows areas of control in Syria and recent airstrikes by the U.S. and Russia; 3c x 3 1/2 inches; 146 mm x 88 mm; (The Associated Press)

In this photo taken from Russian Defense Ministry official web site on Tuesday, Oct. 6, 2015, Russian military support crew inspect missiles attached to their jet at an air base in Syria. at an air base Hmeimim in Syria. A spokeswoman for the Russian foreign ministry has rejected claims that Russia in its airstrikes in Syria is targeting civilians or opposition forces. (Russian Defense Ministry Press Service via AP) (The Associated Press)