A man stabbed and wounded three people at a train station in Winterthur, Switzerland, in what authorities called an “act of terror.”

The suspect, a 31-year-old Swiss-Turkish dual national, was arrested shortly after the attack, which occurred around 8:30 a.m.

Police said he had previously been flagged for distributing Islamic State propaganda and had recently been briefly held in a psychiatric facility.

Three Swiss men were injured, with two later released from hospital and one undergoing surgery for a thigh wound, NBC News has reported.

Authorities believe he acted alone, and officials described the incident as a terrorist attack.