BERLIN — The anti-immigration Alternative for Germany party on Monday sued the domestic intelligence service for classifying it as a right-wing extremist organization, a decision that subjects it to greater surveillance from authorities.
The party known as AfD, which placed second in national elections in February, took action at an administrative court in Cologne, where the intelligence service has its headquarters.
The decision by the intelligence service — formally known as the Federal Office for the Protection of the Constitution — means its officials can now use informants and other tools such as audio and video recordings to monitor the party's activities.
The office warned of a threat to Germany's democratic order, saying the anti-immigration party ''disregards human dignity,'' in particular by what it called ''ongoing agitation'' against refugees and migrants, many from Muslim-majority countries.
In a statement, the party accused the intelligence service of violating the constitution by trying to criminalize what the AfD said was permitted expressions of opinion and criticism of German immigration policy over the last decade.
''With our lawsuit, we are sending a clear signal against the abuse of state power to combat and exclude the opposition,'' party co-leaders Tino Chrupalla and Alice Weidel said, alleging an effort by the service to ''distort democratic competition and delegitimize millions of votes.''
AfD was formed in 2013. Its platform initially focused on opposition to bailouts for struggling eurozone members, but its rejection of a 2015 decision by then-Chancellor Angela Merkel to let large numbers of refugees into Germany helped turn the party into a significant political force.
Far-right parties have been gaining ground across Europe and the AfD attracts international attention, including support from tech billionaire Elon Musk, a close ally of U.S. President Donald Trump.