The police were warned in early March that the 31-year-old Syrian who stabbed three people in The Hague earlier this month was ‘planning a terrorist attack’, the public prosecution department said in a statement on Wednesday.

The report about the man, Malek F, was anonymous and made in broken English, the department said. The information was passed to the security service and discussed with the city council, but the ensuing investigation gave no reason to believe the man had a terrorist background, the department said.

F’s motive for the attack on three random strangers has not yet become clear and he has given differing statements about his action, the Volkskrant said on Wednesday.

A search of his home had not revealed any terrorist materials and no-one has yet claimed responsibility for the attack.

In addition, an anonymous warning without further evidence is not sufficient grounds to arrest someone. At the time of the warning, he was in a psychiatric clinic after throwing all his home furnishings out of the window of his flat.

F is now being treated in the Scheveningen prison hospital after he was shot by police.

His three victims have been released from hospital but will require considerable time to make a full recovery, The Hague mayor Pauline Krikke said.