Though barely a week has passed since MH17 was shot out of the sky over Eastern Ukraine, an aggressive anti-aircraft campaign is still in full swing above the territories controlled by pro-Russian separatists.
On Wednesday, Ukraine's defense ministry said two Su-25 fighters had been blown up by surface-to-air missiles, bringing the count of downed planes, not including MH17, to 14. The incident underscores a stark truth for the international community: the separatist insurgency is armed with an arsenal of growing size and sophistication. The question is: where has it come from?
When rebel brigades and units of Cossack volunteers sprouted in Crimea and eastern Ukraine this year, Russian president Vladimir Putin shrugged off questions about the source of their arms. Shops, he suggested.
But tanks cannot be bought in shops. Nor can anti-aircraft missile batteries of the kind that probably blew Malaysia Airlines flight MH17 out of the sky last week.
Dozens of online images – several of them with location tags in rebel territory and checked by the Financial Times with imaging software to ensure they are recent – confirm large amounts of such equipment now in rebel hands and in use in the fighting in eastern Ukraine.
The Kremlin has repeatedly denied providing arms to the separatists and using undercover operatives on the ground. But western intelligence chiefs say they have little doubt about the origin of the weaponry. The downing of MH17 was achieved, they allege, with sophisticated Russian arms and expertise as part of a smuggling program directed by Russian military and intelligence officials that has seen materiel moved over Ukraine's border in ever-larger amounts in recent months as Kiev's fightback has grown in intensity.
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Among the equipment US intelligence officials believe Russia has supplied are dozens of T-64 battle tanks, Grad rocket launchers, 2S9 Nona self-propelled guns, artillery, BMP-2 infantry combat vehicles with automatic cannons, armored troop carriers, small arms from semi-automatic weapons and mines, and sophisticated anti-aircraft systems.
"The overall strategy – that has been missed by many in the west – has been to create a proper army," said Jonathan Eyal, international director at the Royal United Services Institute, a military and strategic think-tank. "It is not to create a guerrilla organisation. It is not a resistance movement. Russia is trying to create a proper military force."
The numbers of weapons coming into eastern Ukraine – and their capabilities – appear to be anything but small. In the months before the downing of MH17, Russian armament supplies amounted to dozens of vehicles in any given week, according to a Nato intelligence briefing.
The weekend before the Malaysian airliner was shot down, killing the 298 people on board, US intelligence officials said they detected a convoy of "up to 150 vehicles" crossing the border to separatist positions.
"Most of Ukraine's border controls have simply melted away," said Mr Eyal. "Russia has been transporting weapons across on the back of trucks as if it was in the middle of Russia."