Russia ramped up its military buildup in Syria over the weekend, and there are now a total of 28 combat aircraft plus 16 helicopters on the ground, CBS News national security correspondent David Martin reports.
The Russians masked the transport of the military aircraft by flying them in behind transport aircraft, Martin reports, and the speed of the buildup has surprised the U.S.
The Russians appear to be preparing for going after the forces opposing Assad in an effort to prolong his regime. They have spoken publicly about going after the Islamic State of Iraq and Syria (ISIS), which raises the issue of "deconflicting" their flights with coalition flights against ISIS.
For example, a Russian aircraft could attack a moderate opposition group which has been promised air cover by the Obama administration, Martin reports.
The Pentagon said Friday that Secretary of Defense Ash Carter had a "constructive conversation" with his Russian counterpart, Sergei Shoygu, on the situation in Syria and that the two military chiefs had "agreed to further discuss mechanisms for deconfliction in Syria and the counter-ISIL campaign," referring to ISIS by an alternate acronym.
Last week, Russian President Vladimir Putin strongly defended Moscow's military assistance to the Syrian government, saying it's impossible to defeat ISIS without cooperation with Damascus. Russia has staunchly backed up Assad throughout Syria's devastating civil war that has killed about 250,000 people and turned millions into refugees, shielding him from United Nations sanctions and continuing to provide him with weapons despite Western criticism.
Meanwhile, Russia said that its embassy in Damascus has come under shelling that hasn't inflicted any casualties or damage.
The Russian Foreign Ministry said a mine fired from a mortar landed on the territory of the embassy on Sunday. It said the projectile was later removed by the Syrian military.
The ministry strongly condemned the attack, saying in a statement released Monday that it expects the international community to denounce it.
It said that the attack came from militants supported by unidentified "foreign sponsors."