Ukraine Works to Restore Power, Water to Cities After Russian AttacksUkrainian authorities are working to restore electricity and water to key cities, including Kyiv, a day after Russia launched more airstrikes targeting civilian infrastructure. Kyiv Mayor Vitali Klitschko said about 70 percent of the Ukrainian capital remained without power early Thursday. "Energy engineers and specialists worked all night" to restore electricity and water supplies, he wrote on Telegram. Ukrainian Foreign Minister Dmytro Kuleba tweeted Thursday that Russia "wages the most cowardly and barbaric type of war against unarmed civilians." His comments followed President Volodymyr Zelenskyy's appearance by video before the U.N. Security Council during which Zelenskyy said Russian missiles hit hospitals, schools, transportation targets and residential areas. Zelenskyy said Ukraine was awaiting a "very firm reaction" from the world. Russia's U.N. ambassador, Vasily Nebenzya, rejected what he called "reckless threats and ultimatums" by Ukraine and its Western supporters. Russian airstrikes Wednesday knocked out power in multiple Ukrainian cities, including the capital, Kyiv, where authorities said an airstrike killed three people. SEE ALSO: In the western city of Lviv, near the border with Poland, the mayor said the whole city had lost power, although there was no immediate information on how many targets had been hit. Ukraine's Zaporizhzhya nuclear power plant, Europe's largest, once again lost access to external electricity and instead had to rely on its emergency diesel generators for the power it needs for reactor cooling and other essential nuclear safety and security functions, the International Atomic Energy Agency said. IAEA Director General Rafael Mariano Grossi has often called – to no avail – for fighting to be halted near the nuclear plant, to avoid the possibility of a nuclear disaster. SEE ALSO: As the attacks on Ukrainian infrastructure continued, the United States announced that it is sending another $400 million worth of ammunition and generators to Kyiv, bringing the amount of U.S. support to more than $19 billion in assistance during the nine-month war. Some information for this story came from The Associated Press, Agence France-Presse and Reuters.