GENEVA (AP) — Swiss police arrested two people Thursday in connection with a federal investigation into their suspected support for, or participation in, the banned Islamic State group, authorities said.

The police operation, which also involved searches of four houses in the Geneva and Vaud cantons, or regions, was part of a criminal case opened in July last year by the Swiss attorney general’s office.

The case centers on a Swiss-Macedonian dual national and a citizen of Kosovo, who lived separately in the two Swiss regions. The arrests were made in French-speaking western Switzerland.

The two suspects, who were not identified by name, were transferred to the Swiss capital, Bern, for questioning by the attorney general's office, which will decide whether to keep them in custody pending trial.

Switzerland, whose policy of neutrality aims to keep it out of conflicts, has largely avoided the violent extremism that has swept across other parts of Europe.