The investigation into two men from Yemen, arrested at Amsterdam’s Schiphol airport on Monday, is continuing on Wednesday, a spokesman for the public prosecution department told news agency ANP.
The spokesman could not say how long the investigation will continue but officials will have to decide on Thursday if the men should be detained for longer.
There are now strong doubts that the men were involved in a conspiracy to stage a terrorist attack or were testing US airport security.
US officials have now determined the two men missed a connecting flight to Washington from Chicago and were re-routed via Amsterdam. But the luggage of one, Ahmed Mohamed Nasser al-Soofi, did make the Washington flight.
Both men, who are now thought not to have known each other, have strongly denied any involvement in terrorism, lawyer Klaas-Arjen Krikke said on Tuesday evening
According to US media reports, the men will not face charges in the US but the incident involving the men, one of whom had suspicious items in his luggage and the other travelling on an expired visa, points up US aviation’s strengths and weaknesses.