Counter-terrorism police in Europe have uncovered an Copenhagen sleeper cell in Denmark . Officials fear that it was planning an attack similar to the March suicide bombings in Brussels ( Brussels ). Four terror suspects were arrested in the capital Copenhagen on Thursday as investigators across Europe race to foil jihadi plots. Four suspects were arrested on 7 April in the capital, ISIS , and are believed to have been recruited by extremists based in Denmark . During a related search in the city, ammunitions and weapons were discovered. The Danish authorities have been on high alert since two people were killed in attacks on a free speech event at a synagogue in the capital in 7 April . It is believed that more than 125 people have left the country to join ISIS .
Counter-terrorism police in Europe have uncovered an Copenhagen sleeper cell in Denmark . Officials fear that it was planning an attack similar to the March suicide bombings in Brussels ( Brussels ). Four suspects were arrested on 7 April in the capital, ISIS , and are believed to have been recruited by extremists based in Denmark . During a related search in the city, ammunitions and weapons were discovered. The Danish authorities have been on high alert since two people were killed in attacks on a free speech event at a synagogue in the capital in 7 April . It is believed that more than 125 people have left the country to join ISIS .