Cem Özdemir, the Turkish-German co-chairman of Germany’s Green Party, reacted to the spying activities of Turkey’s National Intelligence Organization (MİT) targeting critical Turkish citizens in Germany, saying Turkish informants who believe President Recep Tayyip Erdoğan is so wonderful can go live in Turkey, Deutsche Welle reported.

Voicing support for the “no” campaign for a constitutional referendum on April 16 in Turkey during a program in Duisburg on Wednesday attended by Turks from various ethnic and political backgrounds, Özdemir criticized MİT’s activities in Germany.

“People who have problems with basic rights are not forced to live here. Those who think Erdoğan is so wonderful, they can go live in Turkey. I don’t mean that people who support Erdoğan can’t live in Germany. But informing on those who don’t think the same, trying to oppress and frighten them, is not acceptable,” said Özdemir.

Özdemir also underlined that intelligence services should not be concerned with those who have not committed any crime, but with those who are radicals and terrorists.

Özdemir’s statement came a day after the German Interior Ministry launched an investigation into whether MİT has been spying on suspected supporters of the Gülen movement in Germany.

Speaking in Passau in southern Germany on Tuesday, German Interior Minister Thomas de Maizière said in a report by Reuters that Turkey will not be allowed to spy on Turks living in Germany.

De Maizière said it was a “criminal offense” to carry out espionage activities on German soil and that they “will not be tolerated by us.”

“We have repeatedly told Turkey that something like this is unacceptable. No matter what position someone may have on the Gülen movement, here German jurisdiction applies and citizens will not be spied on by foreign countries,” he said.

According to reports in the German media, the head of Turkey’s MİT, Hakan Fidan, handed Bruno Kahl, the head of Germany’s Federal Intelligence Service (BND), a list of 300 individuals and 200 organizations allegedly linked to the Gülen movement at a security conference in Munich in February, aiming to persuade German authorities to help Turkey.

However, German authorities have informed Turks linked with the Gülen movement about MİT surveillance in Germany, home to 1.4 million voters eligible to vote in the referendum.

Commenting to BBC on the issue on Tuesday, Hans-Georg Maassen, Germany’s head of the German Federal Office for the Protection of the Constitution (Bundesamt fuer Verfassungsschutz), said, “Outside Turkey I don’t think anyone believes that the Gülen movement was behind the attempted putsch.”

“At any rate I don’t know anyone outside Turkey who has been convinced by the Turkish government,” he added.

Tensions rose between Turkey and Germany over operations against Turkish-Islamic Union for Religious Affairs (DİTİB) imams who were claimed to be spying on Gülen movement people.

Last month the coordinator of DİTİB, Murat Kayman, announced his resignation over the charges.