Ukrainian underwater drones have struck two tankers belonging to Russia’s so-called shadow fleet in the Black Sea, according to an official in Ukraine’s security services (SBU).

In Russia, a major oil terminal near the port of Novorossiysk stopped operations Saturday after a strike by unmanned boats damaged one of its three mooring points, according to a statement from the Caspian Pipeline Consortium, which owns the terminal.

The two oil tankers, identified as the Kairos and Virat, were empty and sailing to Novorossiysk, a major Russian Black Sea oil terminal.

Russian forces strafed Ukraine’s capital with a major missile barrage overnight, killing at least three people and causing widespread power outages, as the US ramps up pressure on President Volodymyr Zelenskiy to agree to concessions in the almost four-year-old war.

Ukraine’s chief negotiator, in an exclusive interview, says conceding sovereign territory is off-limits in peace talks.