BRUSSELS, Belgium, Aug 28, 2025 (BSS/AFP) - EU chief Antonio Costa on Thursday said he was "horrified" by a fresh round of deadly Russian strikes on Kyiv that also damaged the bloc's diplomatic mission in the city.

"My thoughts are with the Ukrainian victims and also with the staff of the EU delegation, whose building was damaged in this deliberate Russian strike," European Council president Costa wrote on X.

"The EU will not be intimidated. Russia's aggression only strengthens our resolve to stand with Ukraine and its people."

Costa posted a picture of the inside of an office with the windows blown out, ceiling partially hanging down and debris scattered on the floor.

The EU's ambassador to Ukraine Katarina Mathernova wrote that the delegation had been "severely damaged by the shock wave" of a blast.

An EU official told AFP that none of the bloc's employees had been hurt.

Ukrainian officials said the overnight bombardments -- the second largest of the war -- killed 10 people, including a child.

"While the world seeks a path to peace, Russia responds with missiles," EU top diplomat Kaja Kallas wrote on X.

"The overnight attack on Kyiv shows a deliberate choice to escalate and mock the peace efforts."