Germany’s interior minister has warned his country is host to hundreds of potential Islamist terrorists who could carry out attacks against the European nation.

Thomas de Maiziere told the Bild newspaper there were at least 520 potential attackers currently in the country, according to Reuters.

Another 360 people, he said, were also relevant targets for police due to their ties to potential terrorists.

“The terror threat now stems from foreign hit teams as well as fanatical lone wolves in Germany,” de Maiziere said.

“The hit teams are secretly smuggled into Europe and prepare their actions without being noticed, as we saw with the attacks in Paris and Brussels,” he said. “But it’s even more difficult to uncover the fanatical lone wolves. Unfortunately, there is a real and present danger from both threats.”

Though counter-terrorism officials are monitoring and investigating all known potential assailants, “the authorities are assuming there are undiscovered lone wolf terrorists out there.”

July saw two attacks by migrants in the southern state of Bavaria — an ax rampage on a train in Wuerzburg and a suicide bombing in Ansbach.

In Wuerzburg, the 17-year-old attacker was shot dead by police after injuring five people. In Ansbach 15 people were injured after a failed Syrian asylum seeker detonated an explosive device outside a music festival, killing himself.

Also in July, a teenage German-Iranian gunman killed nine people in a shooting rampage at a busy Munich mall and then committed suicide. Authorities have said it is unclear if the attack was religiously motivated.

AFP contributed to this report.