John Kirby, the White House's National Security Council strategic communications coordinator, said there were "preliminary indications" that the Baku-Grozny flight could have been shot down by Russian air defenses but declined to comment on those signs.
"We have seen initial indications that a Russian air defense system shot the plane down," Kirby said during a briefing.
According to him, the USA has offered to assist in the investigation and respects the work done by Kazakhstan and Azerbaijan.
When asked what kind of signs we discussed, Kirby answered, "These are preliminary signs. I want to be clear: They are only preliminary. The investigation is ongoing, and I don't want to get ahead of myself."