BERLIN (AP) — Two Ukrainian men were stabbed to death in southern Germany, police said Sunday, and a Russian man was arrested by authorities as a possible suspect in the killings.

The two Ukrainians, who were 23 and 36 years old and lived in the southern German county of Garmisch-Partenkirchen, were killed on the premises of a shopping center in the village of Murnau in Upper Bavaria. Shortly after the slayings on Saturday evening, the police arrested a 57-year-old Russian on suspicion of murder, German news agency dpa reported.

The names of the victims and the suspect weren’t released in line with German privacy rules. The possible motive for the killings wasn’t yet known, authorities said. It also wasn’t clear if the three men knew each other.

More than 1 million Ukrainian refugees came to Germany since Russia launched a full-scale invasion of Ukraine in 2022. Germany is also home to a significant Russian immigrant community and 2.5 million Russians of German ancestry who mostly moved to the country after the collapse of the Soviet Union in the early 1990s.