A suspected gunman arrested for killing three people on a Dutch tram this week is believed to have acted with terrorist intent, and authorities are also investigating whether he had other personal motives, prosecutors said on Thursday.

Prosecutors said they believe the suspect, 37-year-old Turkish-born Gokmen Tanis, acted alone in the shooting in the city of Utrecht, but the investigation is still ongoing.

“We are investigating whether the suspect acted solely from a terrorist motive, or whether his actions came out of personal problems in combination with a radicalised ideology,” the prosecutors said in a statement.

Read more: Reuters