Dutch authorities are still trying to determine the motive behind a shooting incident on a tram in the Dutch city of Utrecht in which three people were killed.
"So far, a terrorist motive is seriously being taken into account. This is based on a letter found in the getaway car among other things and the nature of the facts," police and the prosecutor's office said in a joint statement on Tuesday.
Turkish-born main suspect Gokmen Tanis, 37, and two unnamed men from Utrecht aged 23 and 27 remain in custody. Police found a red Renault Clio after Monday's attack which they said the attacker had used to flee.
The three people who died in the shooting were a 19-year-old woman from Vianen, which is near Utrecht, and two men aged 28 and 49 from Utrecht itself, the statement said.
"So far our investigation has established no link between the main suspect and the victims," police and prosecutors added.
Dutch and Turkish media reports had previously reported that a family dispute may have been the motive for the shooting.
However, the police and prosecutors said that "other motives are not excluded, they are also being investigated."
Armed police arrested Tanis in Utrecht after a huge manhunt on Monday during which police released his picture on social media.
"A firearm was found during his arrest," the statement added.
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| Children placed flowers at the site of a shooting in Utrecht [Piroschka van de Wouw/Reuters] |
Public prosecution office spokesperson Ties Kortmann said Tanis is being held on suspicion of manslaughter, but added that investigations were continuing into what drove him to allegedly open fire in a tram.
Authorities said they have not ruled out other possible motives and Dutch media citing his neighbours in Utrecht have speculated that the shooting may have been linked to a relationship.