Prosecutors have freed five of the 12 Somali men suspected of preparing a terrorist attack in the Netherlands.
The prosecutors said they had no evidence of criminal involvement against the five men, but the investigation of the other seven was continuing.
They must decide by tomorrow whether to bring the remaining suspects before a judge or let them go.
The men were picked up in Rotterdam on Christmas Eve after a tip from intelligence services that an attack may be imminent. There was no information on the alleged target, although Rotterdam is one of Europe's biggest commercial hubs with a huge port and large oil and gas storage facilities.
Three of the detainees who had no valid residency permits were turned over to immigration police, prosecutors said. Two of them were residents of Denmark and the residency of the third was not established. Two Dutch residents were released.
On Friday police raided an internet cafe, four homes and two motel rooms but found no weapons or explosives.
It is feared the Netherlands could be targeted by Islamic radicals because of the high-profile anti-Islam campaign by one of the country's most popular politicians, Geert Wilders.
The terrorist alert came one year after Nigerian Umar Farouk Abdulmutallab, who was a student in London, passed through Amsterdam airport on a flight for Detroit, where he allegedly tried to ignite explosives taped to his underwear as the plane was descending toward its US destination.
Heightened nervousness about a terrorist attack, especially on holidays or important anniversaries like the September 11, 2001 attacks in the US, has led to mistakes in the past. Three months ago, police arrested two Yemenis travelling from the US on a request from US law enforcement agencies who feared they were conducting a dry run for a terrorist attack. They were released two days later for lack of any evidence of a crime.
A few weeks later a British man of Somali ancestry was also arrested en route to Uganda after a tip from British authorities. He too was released without charge.