The following is the complete text of the statement published on the homepage of the US embassy in Kyiv, with my comments in italics. Original text here.
United States Assessment of the Downing of Flight MH17 and its Aftermath
We assess that Flight MH17 was likely downed by a SA-11 surface-to-air missile from separatist-controlled territory in eastern Ukraine. We base this judgment on several factors.
The SA-11 designation corresponds to the versions 9K37 Buk and 9K37M Buk-M1.
Over the past month, we have detected an increasing amount of heavy weaponry to separatist fighters crossing the border from Russia into Ukraine. Last weekend, Russia sent a convoy of military equipment with up to 150 vehicles including tanks, armored personnel carriers, artillery, and multiple rocket launchers to the separatist. We also have information indicating that Russia is providing training to separatist fighters at a facility in southwest Russia, and this effort included training on air defense systems.
Note the difference in wording: the US have “detected” the vehicles coming into Ukraine, meaning that they have observed this happening (likely either by satellite, UAV, or boots on the ground). However, they have only “information indicating” the presence of a training facility where air defence systems are taught, signaling a lower degree of certainty. The specific mention of anti-air training given by the Russians to separatists adds credibility to the charges that the Buk-M1 is indeed Russian supplied (and possibly crewed), as opposed to stemming from captured Ukrainian stocks.
Pro-Russian separatist fighters have demonstrated proficiency with surface-to-air missile systems and have downed more than a dozen aircraft over the past few months, including two large transport aircraft.
This is not necessarily relevant. As far as I know, one single transport has been downed at height, the other aircraft and helicopters all having been shot down at low altitude and/or during take-off or landing. The single Antonov An-26 is the sole plane shot down at a height which rules out the use of MANPADS, and it is better described as a medium-sized transport.
At the time that flight MH17 dropped out of contact, we detected a surface-to-air missile (SAM) launch from a separatist-controlled area in southeastern Ukraine. We believe this missile was an SA-11.
This is the core evidence of the statement. The US has detected the launch of a missile from separatist-controlled area happening at the same time the MH17 was downed. It is unclear what kind of intelligence indicates (note the word “believe”) that it indeed was a Buk, but it is still a very strong piece of evidence.
Intercepts of separatist communications posted on YouTube by the Ukrainian government indicate the separatists were in possession of a SA-11 system as early as Monday July 14th. In the intercepts, the separatists made repeated references to having and repositioning Buk (SA-11) systems.
Having perhaps the world’s best intelligence network, and then using easily faked videos of separatist communications posted on YouTube as evidence sure has a degree of ridicule attached to it, but is also an inidcation that US intelligence believes at least some of these transcripts are real.
Social media postings on Thursday show an SA-11 system traveling through the separatist-controlled towns of Torez and Snizhne, near the crash site and assessed location of the SAM launch. From this location, the SA-11 has the range and altitude capability to have shot down flight MH17.
See the earlier post where I discuss some of the OSINT evidence available.
Ukraine also operates SA-11 systems, but we are confident no Ukrainian air defense systems were within range of the crash. Ukrainian forces have also not fired a single surface-to-air missile during the conflict, despite often complaining about violations of their airspace by Russian military aircraft.
Yet another indication that the US is closely monitoring the Ukrainian crises, probably through the use of recce satellites as well as SBIRS. This raises questions about what kind of intelligence the US has on the claimed use of BM-21 Grad MLRS by both the separatists, Ukrainian armed forces, and from Russian territory, as well as the alleged civilian targets these were used against.
Shortly after the crash, separatists – including the self-proclaimed “Defense Minister” of the Donetsk People’s Republic Igor Strelkov – claimed responsibility for shooting down a military transport plane on social media.
In an intercepted conversation that has been widely posted on the internet, a known-separatist leader tells another person that a separatist faction downed the aircraft. After it became evident that the plane was a civilian airliner, separatists deleted social media posts boasting about shooting down a plane and possessing a Buk (SA-11) SAM system.
This is nothing new, but has been openly available since the day of the downing.
Audio data provided to the press by the Ukrainian security service was evaluated by Intelligence Community analysts who confirmed these were authentic conversations between known separatist leaders, based on comparing the Ukraine-released internet audio to recordings of known separatists.
Compared to the brief mentioning of YouTube-videos above, here it is explicitly said that the Intelligence Community have evaluated the videos, and believes these are real.
Video posted on social media yesterday show an SA-11 on a transporter traveling through the Krasnodon are back to Russia. The video indicated the system was missing at least one missile, suggesting it had conducted a launch.
The video is found on my earlier post. Note that in this statement the location of Krasnodon is not doubted, but seen as confirmed.
Events on the ground at the crash site clearly demonstrate that separatists are in full control of the area.
This comes as no surprise for anyone. In itself, it is not evidence of the missile stemming from separatist held territory, the missile has a range of roughly 30-35 km, and the plane didn’t not fall straight down when hit. However, taken into consideration with the other evidence presented here, it does strengthen the case against the Russian-backed separatists.
In conclusion: The US authorities seem sure that the missile was launched by the separatists, but so far lacks hard proof that they were trained in Russia, or that the crew would indeed have been made up of Russian regulars or volunteers.