Did Russia and Ukraine just start a war? What we know and don’t know

On Friday, as a Russian “aid convoy” of 280 trucks neared the Ukrainian border, NATO said that a separate “incursion” of Russian military forces had crossed into Ukraine. The Russian forces are reportedly in eastern Ukrainian territory held by Russia-backed separatist rebels, according to NATO and Ukrainian government officials. Some reports suggest that there may be open fighting between Ukrainian military forces and the Russian incursion, but it’s far from clear whether that’s true or what precisely is happening on the ground.

Did Russia really invade Ukraine outright? Is this now an open war? Here is a running account of what we know and what we don’t know.

— Russia is sending a “humanitarian convoy” to Ukraine, but it seems pretty military. 280 Russian trucks, flanked by attack helicopters, have been moving toward the Ukrainian border. Russia says they’re carrying humanitarian assistance for the people of east Ukraine. Ukraine fears it’s a stealth invasion force. Russia opened up the trucks to journalists, and the BBC reported that they were mostly empty. The convoy earlier stopped at a Russian military base.

— Ukraine claims to have destroyed Russian vehicles Thursday night. In a phone call with British Prime Minister David Cameron, Ukrainian President Petro Poroshenko claimed Ukraine’s military had fired on and destroyed a “significant” portion of “Russian military machines in Ukraine,” allegedly with artillery.

— NATO says Russian troops just crossed into Ukraine. “Last night we saw a Russian incursion, a crossing of the Ukrainian border,” NATO Secretary General Anders Fogh Rasmussen said on Friday. However, this has been going on for some time. Bloomberg reports that these troops weren’t part of the aid convoy.

— Russia is denying that any troops crossed. The Russian defense ministry denies both that any Russian vehicles crossed the border into Ukraine and that any were destroyed there. The official statementreferred to the Ukrainian claims as “some kind of fantasy.”

— Russia has been backing separatist rebels in eastern Ukraine for months. The pro-Russia rebels, who are in many cases Russian themselves, declared independence in cities like Donetsk and have been fighting Ukrainian government forces.

—The Ukrainian military is making a big push to re-take eastern Ukraine. After months of low-level fighting with the rebels, and after the rebels appeared to shoot down civilian airliner flight MH17 over eastern Ukraine, the Ukrainian military has been moving aggressively to expel them. That might help explain why Russia would escalate as well.

— Russia used a stealth invasion force to seize Crimea in March, by quietly sending unmarked special forces into the Ukrainian region. The Russian troops quickly seized the region, expelled Ukrainian forces, held a fraud-ridden referendum on seceding, and annexed Crimea. There are fears Moscow may attempt the same here.

— The UK is taking these allegations seriously. The UK Foreign Office’s Chief Operating Officer, Matthew Rycroft, “summoned” (in his words) the Russian ambassador to the UK and “demanded [an] explanation of reports of Russian military in Ukraine without Ukrainian agreement.”