Russia-Ukraine war at a glance: what we know on day 554 of the invasion

Ukrainian drones strike six regions inside Russia, destroying military aircraft; Kremlin investigating whether plane carrying Yevgeny Prigozhin was downed on purpose

Ukrainian drones struck targets in at least six regions deep within Russia on Wednesday, in one of the largest-scale attacks on Russia in months. Drones hit an airport in the western Pskov region, and the regions of Moscow, Oryol, Bryansk, Ryazan and Kaluga.

The strike on the city of Pskov started a fire and damaged four Il-76 military cargo aircraft, Russian authorities said, engulfing two of the planes in flames. Footage and images posted on social media showed smoke billowing over the city and the regional governor, Mikhail Vedernikov, ordered all flights to and from Pskov airport to be cancelled on Wednesday.

Three drones came down in the Bryansk region, according to the Russian military, and two over the Oryol region, its governor, Andrei Klychkov, said. One came down in the Ryazan region, one more in Kaluga, and one more in the Moscow region, officials said. No damage or casualties were registered.

At least two people were reported killed in Kyiv in what authorities described as the heaviest series of Russian airstrikes on the Ukrainian capital for months. Air defences shot down all 28 Russian missiles and 15 out of 16 drones, Gen Valerii Zaluzhnyi, commander-in-chief of Ukraine's armed forces, said on Wednesday.

Six Ukrainian pilots were reportedly killed when two military helicopters crashed in the eastern Donetsk region. According to the Ukrainska Pravda newspaper, the two Mi-8 helicopters crashed in Kramatorsk on Tuesday. The aircraft were completely destroyed and the bodies of six dead servicemen were found.

The chief official in Crimea, annexed by Russia in 2014, said a cruise missile was fired at the peninsula on Wednesday. Anti-aircraft forces in eastern Crimea have downed a cruise missile," Sergei Aksyonov said on Telegram and asked residents to remain calm.

Russian investigators are considering the possibility that the plane carrying the Wagner mercenary head Yevgeny Prigozhin was shot down on purpose, the Kremlin said on Wednesday in the first explicit acknowledgment of what most already believed to have been an assassination. It is obvious that different versions are being considered, including ... a deliberate atrocity," the Kremlin spokesperson Dmitry Peskov told reporters.

EU imports of Russian liquified natural gas (LNG) have increased by 40% since the invasion of Ukraine. Member states have bought more than half of Russia's LNG on the market in the first seven months of this year, according to analysis. Spain and Belgium, which acts as major gateways for LNG supplies to the EU, have emerged as the second and third-biggest customers of Russian LNG respectively after China.

The Wagner group is expected to remain operational in Africa, the EU high representative for foreign affairs and security policy and vice-president of the European Commission said. They will remain operational in Africa because it is the armed wing of Russia," Josep Borrell said.

Russia is in secret, active talks with North Korea to acquire a range of munitions and supplies, the White House has said. Arms negotiations between Russia and the DPRK are actively advancing," the White House national security spokesperson, John Kirby, said, adding that a key focus of the talks was artillery ammunition.

Tech companies including TikTok and Twitter failed to effectively tackle Russian disinformation online during the first year of the war in Ukraine, according to a study published on Wednesday by the EU. The independent study for the EU comes after tougher rules under its Digital Services Act (DSA) kicked in this month for the world's biggest online platforms.

The Russian foreign minister, Sergei Lavrov, and his Turkish counterpart will discuss a proposal by Moscow for an alternative to the Black Sea grain deal when they meet this week, Lavrov's ministry has said. Under the plan, Russia would send a million tonnes of grain to Turkey at a discounted price, with financial support from Qatar, to be processed in Turkey and sent to countries most in need, the foreign ministry said.