Three people have been killed following a shooting on a tram in the central Dutch city of Utrecht, the city's mayor says.
Nine others were injured in the incident which police say appears to be a terrorist attack.
Police are looking for a 37-year-old Turkish man named as Gokmen Tanis and have warned people not to approach him.
Schools have closed and security has been increased while counter-terrorism police work to find the gunman.
"We cannot exclude a terrorist motive," Dutch anti-terrorism co-ordinator Pieter-Jaap Aalbersberg told a news conference on Monday.