A top Ukrainian drone commander said on Tuesday that his forces have used uncrewed aerial vehicles to knock out 300 ships in Russia’s “shadow fleet” over 11 weeks.

Maj. Robert “Magyar” Brovdi, commander of Ukraine’s Unmanned Systems Forces, said as drone crews reached this tally after they attacked and “burned” 21 tankers over the last three days.

The strikes have been part of a Ukrainian campaign from early July targeting the hundreds-strong fleet of merchant tankers assessed to be carrying sanctioned Russian gas and oil.

While many of these vessels access Russia from the Baltic, the Ukrainian effort has focused on the Black Sea and the Sea of…