The Pentagon acknowledged Monday that Russia has been building up a military base in Syria.
Pentagon spokesperson Captain Jeff Davis said that the U.S. has seen a "continued steady flow" of equipment and people for the past week and a half.
Davis would not say how many people or give specifics on what types of equipment are moving in to the Latakia area, but he did say that the flow "suggests the establishment of a forward-operating air base."
He said that the U.S. is concerned about "deconfliction" of airspace, but would not comment on whether the coalition has invited Russia to join the air campaign against ISIS in Syria. Davis did say that the U.S. would "welcome Russia's participation in the global anti-ISIL efforts."