Thirteen people have been detained in Denmark and another in Germany on suspicion of planning one or more terrorist attacks, officials in both countries announced on Friday.
"Our security authorities have once again prevented an Islamist terrorist attack," German Interior Minister Horst Seehofer said
The suspects held in Denmark were detained during a large anti-terrorism operation over the weekend and are accused of acquiring "ingredients and components for the manufacture of explosives as well as weapons" or being accomplices to planned terrorist acts, the Danish security service PET said.
"We have found ingredients aimed to make bombs. We have also seized weapons like pump guns and a hunting rifle," Flemming Drejer of the PET told a press conference.
The PET believed the planned attacks had an Islamist motive.
Seven people - four men and three women - were on remand until March 2, the PET announced on Thursday.
Early on Friday, a Danish court ordered another four men and two women on remand until February 23.
Drejer said a court order prevented them from giving details about the suspects, but they were linked.
Three brothers from Syria
Police in Germany said on Thursday that three brothers from Syria had been arrested at the weekend - two in Germany and one in Denmark - on suspicion of having jointly prepared an explosives attack.
Lene Sorensen of the Danish Central and West Zealand Police told reporters they had cooperated with the PET and several locations were searched.
Danish Justice Minister Nick Haekkerup earlier thanked German authorities for cooperating with the PET, and that the case showed that "the terrorist threat against Denmark remains serious."
The district court in Dessau-Rosslau in the German state of Saxony-Anhalt, where one of the brothers detained in Denmark had resided, had already issued an arrest warrant for the three men, aged 33, 36 and 40.
They stand accused of preparing a serious act of violence against the state, the federal public prosecutor in the city of Naumburg said.
Chemicals from Poland
The three brothers are said to have participated in the purchase of several kilograms of chemicals in Poland in January, leading investigators to believe they planned on building a bomb.
The goods were then transported from Poland to Dessau-Rosslau and onwards to Denmark, according to the investigation.
Two of the brothers first travelled to Germany in 1998 and the two Syrian nationals later received protected status as refugees. One is said to have married a German woman.
Members of the family were already flagged by authorities as Islamists between 2006 and 2016. However, any suspicion of illegal activity could not be substantiated at that time, according to security sources.
"Terrorism is international - and so is our counterterrorist programme," Seehofer said.
German authorities were informed about the sale of the chemicals by their counterparts in Poland. Shortly afterwards, contact was established with investigators in Denmark, where the focus of the probe is now based.