Aftermath of a Russian missile and drone attack in Kyiv (Reuters image)Russian drone attacks killed at least five people across Ukraine early Monday, including an Egyptian sailor aboard a cargo vessel in the Black Sea and a family of three in the northern Sumy region, Ukrainian authorities said.The latest strikes come as Moscow and Kyiv continue to intensify aerial attacks despite stalled US-led efforts to revive peace negotiations aimed at ending Europe's deadliest conflict since World War II.According to Ukrainian Deputy Prime Minister Oleksii Kuleba, a Russian drone struck a Panama-flagged vessel in the Black Sea, triggering a fire and killing an Egyptian crew member."A drone strike set fire to a vessel sailing under the flag of Panama. A crew member was killed -- a 58-year-old cook, a citizen of Egypt," Kuleba said on Telegram.He added that eight other sailors, including citizens of Turkey and India, escaped on a life raft after abandoning the vessel, which suffered extensive damage.The ship "sustained significant damage and lost seaworthiness", Kuleba said.In a separate attack, a Russian drone strike killed three members of the same family in Ukraine's Sumy region, according to the regional prosecution service.The victims were identified as a 13-year-old boy, his 36-year-old father and his 73-year-old grandmother."The 31-year-old mother of the deceased boy, his 10-year-old brother, and 13-year-old sister were also injured," the prosecution service said.Further south, a Russian drone attack set a residential home on fire in the city of Zaporizhzhia, killing a woman, regional authorities said.Drone attacks intensify on both sidesThe latest strikes are part of a broader escalation in drone warfare between Russia and Ukraine, with both sides launching large-scale attacks in recent weeks.In Russia, aviation authorities temporarily shut down all four airports serving Moscow after air defence systems intercepted a wave of Ukrainian drones.Russia's defence ministry said its air defences destroyed 301 Ukrainian drones overnight.Meanwhile, authorities in the Russian-annexed Crimean Peninsula announced new restrictions after a series of Ukrainian attacks on Russian energy infrastructure.Moscow-installed officials said fuel sales had been suspended on Sunday following repeated strikes on oil refineries. On Monday, authorities also announced the suspension of organised children's summer trips to Crimea due to the deteriorating security situation.Peace efforts remain stalledThe renewed attacks come as diplomatic efforts to end the conflict remain largely frozen.Russian President Vladimir Putin has repeatedly rejected calls from Ukrainian President Volodymyr Zelensky for direct peace negotiations, insisting that Russia will pursue its military objectives on the battlefield.With both sides continuing long-range drone and missile attacks, prospects for a near-term breakthrough in peace talks remain uncertain.