Police in Denmark and Germany have arrested a total of 14 people on suspicion of planning an Islamist bomb attack.
Thirteen of the arrests were made in Denmark during a major counter-terrorism operation carried out last weekend in the greater Copenhagen suburbs, the Danish Security and Intelligence Service (PET) said.
One other person was arrested in Germany.
German Interior Minister Horst Seehofer said the country's security services had "again avoided an Islamist terrorist attack".
In Denmark, suspects were remanded in custody "for planning one or more terrorist attacks or participating in an attempted terrorist act", according to PET.
They are accused of having "acquired ingredients and components for manufacturing explosives, as well as firearms or having aided and abetted in the offence".
Six other people "linked to the case" were brought before a judge in Holbaek, PET added.
'Planning attack in Europe'
Three Syrian brothers, aged 33, 36 and 40, are among those arrested; two in Denmark and the third in Hesse, a region in central Germany.
Seehofer said the brothers "were probably preparing an attack in Europe".
The three men are suspected of preparing "a serious act of violence endangering the state", according to the public prosecutor's office in Saxony-Anhalt. In particular, the suspects are accused of purchasing several kilograms of chemicals in January used to make explosives.
Subsequent searches in Denmark and the German town of Dessau also found "ten kilograms of black powder" and other chemical components.
In a press conference on Friday, Danish police added that they had also found weapons and an Islamic State group flag that could indicate the suspects "have a connection or sympathy with the terror organisation".
Flemming Drejer, operative head of the PET, said the findings were "worrying'' but "it is our assessment that there was no imminent danger".
Case in secrecy
The identities and nationalities of the other suspects have not been made public, and neither country has specified possible targets for the attack.
"The cooperation between PET and the German authorities has been excellent and efficient," PET said in an earlier statement.
"We believe that there are individuals with the intent and capacity to commit terrorist attacks in Denmark. It is PET’s assessment that the terror threat to Denmark is significant, and the case at hand does not change this assessment."
Danish Justice Minister Nick Haekkerup also expressed his gratitude to Danish and German authorities on Twitter.
"The case, unfortunately, shows that the terrorist threat against Denmark is still serious", said Haekkerup.
All the detention hearings in Denmark were held behind so-called double closed doors, meaning the case is shrouded in secrecy and few details are made public.