Warsaw: A privately chartered train traveling from Kyiv toward Poland on Sunday with Former British Prime Minister Boris Johnson and European officials aboard was stopped due to a drone attack threat, German newspaper Der Spiegel reported.

According to Anadolu Agency, Gunter Sautter, one of German Chancellor Friedrich Merz's closest advisers, was traveling overnight from Kyiv toward Poland on a privately chartered train when it stopped early in the morning at the Polish border. Parts of the train were evacuated following drone strikes in the area.

The security measure came after an incident on the same railway line. Early Sunday morning, a drone attacked a passenger train traveling from Kyiv to Warsaw near the Polish border. According to the operator, the locomotive was hit. No one was injured.

Sautter, a foreign and security policy adviser at the Chancellery, had been in Kyiv with security advisers from Britain, France, and Italy for talks with Ukrainian President Volodymyr Zelenskyy's government on possible peace negotiations with Russia. He also attended the Yalta European Strategy conference Saturday.

Other European security advisers, German lawmakers, diplomats, and academics were aboard the train, along with Johnson, who was returning to Poland after the conference.

No one was injured, the newspaper reported, adding that the passengers were briefly evacuated after a drone alert before authorities issued an all-clear when no further drones were detected.