There’s strong evidence it was pro-Russian rebels responsible for the attack.
From Sky News.
A plane which crashed in eastern Ukraine with 295 people on board was reportedly shot down as it flew through or near airspace deemed unsuitable for passenger jets.
The Malaysia Airlines plane, which was flying from Amsterdam to Kuala Lumpur, was traveling at an altitude of 33,000 feet (10,000 metres) when it was brought down, Russia’s Interfax reported.An adviser to the Ukrainian interior ministry told the news agency the Boeing 777 was brought down by a Buk ground-to-air missile, killing all 280 passengers and 15 crew members.
There are reports of British victims, as well as 23 Americans, although the passenger manifest for flight MH17 has not yet been released.
Plumes of thick, black smoke could be seen rising high into the air near the village of Grabovo, Donetsk.

The plane, which one eyewitness said split in two on impact, is almost unrecognisable in pictures of the crash site, with burning wreckage scattered across a vast area.
……Officials in Kiev were quick to deny any involvement, with Ukrainian President Petro Poroshenko lamenting what he called an “act of terrorism”.
However, Alexander Borodai, the eastern Ukraine separatist leader, said the aircraft was shot down by government forces – a claim backed by a separatist from Krasnyi Luch, who told the Reuters news agency that rebels do not have weapons capable of shooting down a plane at such height.
What a co-ink-i-dink:
Rebels from the separatist Donetsk People’s Republic (DPR) overran a Ukrainian army garrison on June 29 and claimed to have captured at least one such weapon. They then posted a Twitter picture of the missile system, which was deleted yesterday as reports of the downed airliner spread.
Putin is already engaged in a propaganda offensive, making the fatuous claim that it was his plane that Ukrainian separatists tried to shoot down. Funny, his plane was no where in the vicinity when the rockets were launched.
Obama was at the start of a stump speech in Delaware, when he dedicated about 40 seconds to the ‘tragedy’ then he quickly returned to his lighthearted prepared remarks which were riddled with jokes about ‘good-looking Bidens’ in the crowd and Jack Lew’s illegible signature on treasury notes, before he launched into a 16 minute speech whining about Republican objections to his 5 1/2 year shredding of the Constitution. Reminds me of the flippant attitude he displayed during a speech he gave just after learning of the Ft. Hood terrorist attack. The gravity of threats to the West around the world doesn’t register in his frayed psychological tapestry.
The social media response has been justifiably harsh:
National Review reporter Charles Cooke tweeted: ‘Shorter Obama: ‘Something awful has happened with a plane. It’s awful. Awful. Republicans are bastards for not funding new airports”.
‘Traveling in Denver, this reporter heard gasps from guests watching a hotel lobby television as Obama spoke.
One remarked: ‘A tragedy is when you lose control and fly into a mountainside. This is mass-murder. What a disappointment.’
His distance from reality is just bizarre,’ said another.
Barky Obama will go through his usual spiel about sanctions, blah… blah… blah….”this time we really mean it”…blah blah blah…while Vladimir Putin laughs and bitch-slaps him again.
It’s no pleasure watching a pusillanimous excuse for a “president” getting owned by Putin on a regular basis.
If you think Russia will be punished for this latest atrocity, don’t hold your breath.
Gee, if only the GOP had a fraction of Putin’s guts, Obama would have been prosecuted and imprisoned by now, for all the crimes he’s committed.
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to quote the future presidunce…
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what difference does it make???…