PRYLUKY, Ukraine (AP) — At least five people, including a 1-year-old child, his mother and grandmother, were killed Thursday in a nighttime Russian drone attack on the northern Ukrainian city of Pryluky, officials said.

Russian President Vladimir Putin told US President Donald Trump in a phone call Wednesday that Moscow was obligated to respond to Ukraine’s weekend drone attack, Trump said, setting up a potential escalation in the conflict just as the US president hopes to broker an end to the war.