Fifteen people were killed and seven wounded after a Russian drone struck a bus carrying miners in Ukraine’s southeastern Dnipropetrovsk region, energy firm DTEK ​and government officials said on Sunday.

The attack came hours after Ukrainian President Volodymyr Zelenskyy announced that a ⁠second round of U.S.-brokered trilateral talks between Ukraine and ‍Russia would ⁠take place next week.

DTEK ​said in a statement that Russian forces had carried out a “massive terrorist attack” on a company mine in the region and that all of the dead and wounded ⁠were its employees returning from a shift.

“Today, the enemy carried out a cynical and targeted attack on energy sector workers in ‍the Dnipropetrovsk region,” Energy Minister Denys Shmyhal wrote on the Telegram messaging app.