The Ukrainian Foreign Ministry sent reporters a link to the edited audio of the calls, with English subtitles, posted on YouTube by Ukraines intelligence agency, the State Security Service, known as the SBU.
The audio, purportedly recorded soon after the civilian jetliner with 295 people on board went down in the warzone close to the Ukraines border with Russia, added to Ukrainian and Western suspicions that pro-Russia separatists were culpable.
American intelligence and military officials said the plane had been destroyed by a Russian SA-series missile, based on surveillance satellite data that showed the final trajectory and impact of the missile, but not its point of origin.
There were strong indications that those responsible may have errantly downed what they had thought was a military aircraft only to discover, to their shock, that they had struck a civilian airliner.
Russias President Vladimir Putin blamed Kiev for creating what he called conditions for insurgency in eastern Ukraine. He did not specifically deny that a Russian-made weapon had felled the passenger jet.
According to a translation of the Russian audio by the English-language Kyiv Post, the recording begins with a separatist commander, identified as Igor Bezler, telling a Russian military intelligence official, Vasili Geranin, We have just shot down a plane.
In a second audio clip, a man apparently at the scene of the crash is heard saying Cossack militiamen from the village of Chernukhino were responsible. The plane fell apart in the air... We have found the first 200, a man described as Major in the subtitles, says, using what is apparently a code word for a dead person.
...It was definitely a civilian aircraft, Major says. There are remains of internal brackets, seats and bodies. Asked if there were any weapons in the debris, Major replies: Absolutely nothing. Civilian items, medical stuff, towels, toilet paper.
Myroslava Petsa, a Ukrainian journalist in Kiev, said that the people in the audio sounded shocked by what they had found in the wreckage.
By Thursday night, American intelligence analysts were increasingly focused on a theory that rebels had used a Russian-made SA-11 surface-to-air missile system to shoot down the aircraft and operated on their own fire-control radar, outside the checks and balances of the national Ukrainian air-defence network.
(Separatist rebels who control the area said on Friday, meanwhile, that they had recovered most of the planes black boxes and were considering what to do with them, The Associated Press reported. Their statement had profound implications for the integrity of the crash investigation. Ukraine, whose investigators have no access to the area, has called for an international probe to determine who attacked the plane.)
SABRINA TAVERNISE, ERIC SCHMITT & RICK GLADSTONE