As the war enters its 771st day, these are the main developments.

Fighting

• The death toll in a Russian drone attack on Kharkiv rose to four, including three rescue workers who were killed in a second strike after they’d gone to provide assistance following the initial attack. Governor Oleh Synehubov said 12 people were injured, with three in serious condition. The attack also cut power to about 350,000 people.
• In separate incidents, four people were killed in Russian artillery fire and aerial bomb attacks in the regions of Donetsk, Kharkiv and Sumy, according to local officials.
• Moscow-installed officials in Russian-occupied parts of eastern and southern Ukraine said a total of six civilians were killed in Ukrainian drone and shelling attacks.
• Vasily Golubev, the governor of Russia’s Rostov-on-Don region bordering Ukraine, said air defence destroyed more than 40 airborne targets. An electricity substation in Morozovsk district was hit and work was under way to restore power supplies, he added.
• Border police in Moldova said they found what appeared to be fragments of an Iranian-made Russian drone about 500 metres (1,600 feet) from the border with Ukraine. The area was cordoned off.

Politics and diplomacy

• Russian Foreign Minister Sergey Lavrov said China’s 12-point peace plan, released on the first anniversary of Russia’s full-scale invasion of Ukraine, was “reasonable” because it was “based on an analysis of the reasons for what is happening and the need to eliminate these root causes”. Critics have called the plan vague.
• An investigation by Monitor magazine and shown on public broadcaster ARD said two German construction companies were involved in rebuilding the Ukrainian city of Mariupol, which Russia seized two years ago after a weeks-long siege that killed thousands and left the city in ruins.
• Ukraine said it sentenced a resident of the eastern city of Kramatorsk to life in prison after he was found guilty of high treason for helping Russia target a missile strike on a pizzeria last June killing 13 people and injuring dozens more.
• Switzerland’s population grew last year at its fastest rate in 60 years, pushed by record immigration including thousands of people from Ukraine, according to preliminary figures from the Federal Statistics Office.

Weapons

• Czech Prime Minister Petr Fiala said Prague will donate tens of millions of euros to an initiative it is leading to buy hundreds of thousands of artillery ammunition rounds for Ukraine. The first deliveries are expected by June.
• NATO members agreed to scour their arsenals to provide more air defence systems to help Ukraine protect itself from Russian ballistic missile attacks but provided no specific targets or pledges.