Dutch police say they have foiled an attempt to commit a major terrorist attack with AK47 machine guns, grenades and a car bomb.
Officers arrested seven suspects, aged between 21 and 34, who they say planned to attack an event with guns and grenades, and detonate the car bomb in a different location.
Dutch prosecutors were tipped off by intelligence services who said the ringleader wanted to hit "a large event in the Netherlands where there would be a lot of victims".
Counter-terror authorities said: "In the Netherlands, jihadist networks operate with the intention of planning attacks in Europe. These arrests must be seen in that light."
The suspects were allegedly led by a 34-year-old man of Iraqi origin from Arnhem, who was convicted last year for trying to travel to Isis-held territory. Two other suspects made similar attempts.
The suspects were arrested in Arnhem in the east of the Netherlands and in Weert, a region close to the Belgian border, the Dutch public prosecutors' office said.
The men were arrested in raids led by Dutch anti-terror police, who were supported by helicopter and observation teams.
They were found with five pistols after an investigation that lasted months.
Surveillance was stepped up this month as the suspects were believed to be searching for grenades, raw materials for the car bomb and weapons including the Kalashnikov guns. They were also believed to be looking for weapons training.
Minister for Justice and Security Ferd Grapperhaus told Dutch national broadcaster NOS that police acted in time to prevent an attack.
"In a sense it is serious, but luckily it's also good news - a terrorist cell that was plotting an attack has been taken down," Grapperhaus said.
"They weren't so far that it was a danger to society, in the sense that it was nearly too late.
"But they were quite far in their preparations."
The current threat level in the Netherlands is set at four, which means the chance of an attack is real.
The men were to be brought before a court in Rotterdam overnight and were only allowed contact with their lawyers.
In June this year, Europol said the risk of attacks by Isis (Islamic State) remained acute in Europe.
Earlier this month an Isis terrorist was shot by Dutch police after stabbing two American tourists in Amsterdam.
Jihadists involved in the 2015 Paris terror attacks, which were a series of co-ordinated attacks with guns and explosives around the French capital, were traced back to neighbouring Belgium.
The European Union's police agency said that Islamist attacks in Europe more than doubled last year, when 33 terrorist incidents were reported. Ten attacks were successful and killed a total of 62 people.