Conflicting reports from unnamed U.S. officials regarding Russia’s involvement in the Syrian chemical weapon attack highlight the increasingly tenuous political situation the United States and Russia find themselves in.

After an anonymous U.S. official told news organizations that Russia knew in advance that Syria intended to gas civilians, and then participated in a cover up operation, other government sources refuted the claim, saying there was no indication of a direct Russian link.

The initial claim of Russian complicity came after a surveillance drone was seen observing a Syrian hospital that was receiving victims of the gas attack. Shortly after the victims arrived, the hospital was bombed by a Russian-made jet.

The anonymous source said that Syrian forces do not possess such advanced drone technology, and the bombing of the hospital is proof of direct Russian involvement. By killing the victims of the gas attack, it is theorized, the attack itself could be covered up.