MH17: the knowns and unknowns thus far

Malaysia Airlines flight MH17 was shot down over Ukraine on Thursday, say American intelligence, while en route from Amsterdam to Kuala Lumpur.

The plane was carrying 298 people and had taken the usual daily route, flying at least 300m above the 9,700m limit over Ukrainian airspace.

The following is a list of what's confirmed and unconfirmed as of Friday morning, as reported by the Vox website.

The knowns

Malaysia Airlines flight MH17 leaving Schiphol Airport in Amsterdam, the Netherlands, on July 17, 2014.

* MH17 was shot down in Ukraine with 298 on board, and Ukrainian sources say there appear to be no survivors.

* MH17 was travelling from Amsterdam to Kuala Lumpur.

* Malaysia Airlines lost contact with the plane at 14.15 (GMT) at 30km from the Tamak waypoint, approximately 50km from the Russia-Ukraine border, according to MAS.

* US intelligence agencies confirmed that a surface-to-air missile took down the jet, but they are divided on who fired it, according to the Wall Street Journal. Vice-President Joe Biden described the jet as "blown out of the sky".

* Ukrainian officials are blaming pro-Russia separatists for the crash. An intercepted phone call (audio here) between a separatist leader and a Russian security official indicates they were responsible, but it's still not verified.

* Reuters reports that 23 people who died in the crash were American citizens. President Barack Obama, in an address in Delaware, did not confirm this number, but said the government was working to determine if Americans were on the plane. It's confirmed the plane had Dutch, Australian, Malaysian, Indonesian, British, German, Belgian, Filipino, and Canadian passengers. Here are the current verified nationality counts.

* "A civilian airliner traveling from Amsterdam to Kuala Lumpur has just been shot down by a Buk anti-aircraft system," Ukrainian Interior official Anton Gerashchenko said to Interfax-Ukraine news.

* Rebels are denying responsibility. "We simply do not have such air defence systems," they're quoted as saying in a tweet from New York Times reporter Ellen Barry sourced to Interfax.

* The rebels had previously claimed to have a Buk system, according to a June 29 report sourced to the rebel Donetsk People's Republic press service.

* The BUK surface-to-air missile system is a "sophisticated system requiring a whole suite of radar and command vehicles," according to the US embassy in Kiev. In other words, this isn't some shoulder-fired missile in the style of ragtag militias – it takes real training and resources to use.

* Rebels had previously said they were shooting at Ukrainian fighter jets with rockets, including "two or three" on Wednesday evening, the day before the MH17 crash, the New York Times reported. The Ukrainian government said last week that two of its military aircraft had been shot down, although it is unclear whether by Russians or by Ukrainian rebels.

* Russia is denying responsibility for the MH17 disaster. "We didn't do it," Russian UN Ambassador Vitaly Churkin said, according to the Financial Times. President Vladmir Putin is blaming Ukraine for the attack.

* Obama has already spoken with Putin, as well as President Petro Poroshenko of Ukraine and Prime Minister Datuk Seri Najib Razak of Malaysia, about the crash.

* Russia has had thousands of troops stationed just across the border since the crisis in eastern Ukraine began. Nato says Russia had recently increased its force on the border to between 10,000 and 12,000 troops.

* A VK account associated with Ukrainian rebel commander Igor Strelkov appeared to take credit for shooting down a plane over Ukraine earlier today, but later deleted the post.

Here's an analysis of what this might mean.

The unknowns

* Who fired the missile and where from. The Wall Street Journal is reporting that a surface-to-air missile was launched. Intelligence agencies are reportedly divided on whether the missile was fired by Russia or eastern Ukraine.

* Did the Strelkov VK account intend to take credit for shooting down the Malaysian Airlines flight or was it just tough-talking? Was it speaking officially for Strelkov himself or just whoever was running the page? Why did they delete the post?

* How many Americans, if any, were on board the aircraft? The released counts of passengers by nationality so far do not add up to 298 – there are still 47 passengers whose nationalities are unknown.

* No one knows how any of the major players – including the United States, Russia, and Ukraine – will respond to the incident. A lot may depend on who was ultimately responsible for the attack.

* It's not clear how, or whether, this will change Russia's relationship with the rebel groups in eastern Ukraine, which Moscow has been supporting. It's not clear how Europe and the US will respond if the plane was shot down by Ukrainian rebels or, even more consequentially, by forces inside of Russia. It's not clear how this will affect political dynamics within Washington, where Republicans have been pressuring the Obama administration to take a tougher line with Moscow. – July 18, 2014.