Published: 18:52 EST, 17 July 2014 | Updated: 04:00 EST, 18 July 2014
U.S. Senator John McCain said Thursday that there would be 'hell to pay, and there should be,' if Russian forces or pro-Russian separatists in Ukraine were behind the missile attack that brought down Malaysian Airlines flight 17.
'This was an airliner headed towards Russian airspace,' the Arizona Republican said on MSNBC. 'And it has the earmarks – and I'm not concluding – but it has the earmarks of a mistaken identification of an aircraft that they may have believed was Ukrainian.'
'If that's true, this is a horrible tragic event which was certainly unanticipated by anybody no matter who they are. And there will be incredible repercussions if this is the case.'
'If it is the result of either separatist or Russian actions mistakenly believing that this is a Ukrainian warplane,' McCain warned, 'I think there's going to be hell to pay and there should be.'
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McCain unleashed: The hawkish senator warned that there would be 'hell to pay' if Russia or its proxies were responsible for downing a passenger plane
A Russian 'Buk' air defense missile like this one is believed to have shot down Malaysian Airlines flight 17, with Russia and Ukraine pointing fingers of blame at each other
The senator's comments came as recovery workers began to pick through mounds of luggage, airplane sections and even human remains in a nine-mile debris field where the Boeing 777 went down Thursday.
He also told host Andrew Mitchell that President Barack Obama has mishandled the Ukraine crisis by going soft on Russian President Vladimir Putin and refusing to arm Ukrainian government forces.
'The United States – it has been insulting in how small and how little help we have given,' he complained. 'I mean, they have been begging us for defensive weaponry [but] we have not given it to them.'
He also slammed the White House for the shallowness of economic sanctions the U.S. has pushed on Moscow after Putin annexed a region of Ukraine that was populated mainly by ethnic Russians.
'The sanctions so far in exchange for Crimea have been minuscule,' said McCain.
'These latest enacted by the Obama administration, I think, are helpful. But if you ask the Ukrainian government that's struggling, they said they need weapons [with] which to defend themselves.'
Earlier in the day McCain went directly after Putin, telling Roll Call that if the plane was fired on by 'separatists, which are also Russian, Vladimir Putin should be paying a heavy price.'
He also cautioned that it was too soon to know for sure what happened as the aircraft, carrying 295 souls between Amsterdam and Kuala Lumpur, flew at 32,000 feet over the easternmost part of Ukraine and nearly into Russian airspace.
Russia's President Vladimir Putin (R) talked to Russia's Prime Minister Dmitry Medvedev after word reached Moscow of the attacked aircraft
Wreckage: Firefighters contained blazes at the site of the crash near the town of Shaktarsk, in rebel-held east Ukraine
Putin on Thursday called the idea of Russian government involvement in the plane's destruction 'stupiditry' and blamed Ukraine.
'This tragedy would not have occurred if there was peace in that land,' he said, at least if hostilities had not resumed in the southeast of Ukraine.'
'And without question, the state over whose territory this took place bears responsibility for this awful tragedy.'
U.S. officials said Thursday that they are certain the passenger plane was shot down by a Russian-made surface-to-air missile.
The Associated Press reported that Soviet-era 'Buk' missile systems have been spotted in an area of eastern Ukraine controlled by separatist fighters.