The Islamic State caliphate may have fallen in the Middle East, but the terrorist group still strikes fear in Germany.

A newly released German government intelligence report for 2018 finds a high level of danger from ISIS returnees. Of the more than 1,000 Germans who traveled to Syria and Iraq to fight for the terrorist group, 350 are back in Germany. Others have died, or remain in Kurdish prisons, mainly in Syria, with a small number in Iraq.

Some of the returnees are in German jails, while others await trial. Some are in hiding after slipping through the European Union’s porous borders. The German government has admitted having completely lost track of more than 160 of the former ISIS militants, the DW reported.

FEMALE JIHADISTS ARE JUST AS 'MOTIVATED' TO BUILD AN ISLAMIC STATE AS MEN, REPORT CONCLUDES

The report by Germany’s domestic security agency, Bundesamt fur Verfassungsschutz (BFV), warns that the returnees, who are glorified by domestic radical Islamic groups, may commit crimes.

“They are greeted as heroes because they fought for an Islamic state,” Deidre Berger, director of the Berlin office of the American Jewish Committee (AJC), told Fox News.

The report states that in regards to the risk of returnees, "the picture is heterogeneous."

"The spectrum is assessing these persons ranges from the 'disillusioned,' whose activities significantly decline after return and/or are no longer detectable, to persons with combat experience ready to commit violence," it says. "In principle, it must be assumed that Islamist attitudes prevail in most cases. Their ability to move inconspicuously in Western countries, from the jihadi groups' perspective, predestines the returnees to plan and commit attacks in their home countries."

FOUR SUSPECTED ISIS MEMBERS ARRESTED IN NICARAGUA, WERE POSSIBLY HEADED FOR THE US

Among those who welcome these fighters is Germany’s growing community of Salafists – Muslim fundamentalists who shun German secular life and pose security threats.

The Islamic state for which the returning Germans fought was guilty of atrocities that were often videotaped and seen around the world. A trial in Munich provides an example of one atrocity.

A German woman identified as Jennifer W. bought a five-year-old Yazidi girl as a slave and chained her outside for bedwetting. The girl died of thirst in the scorching heat. Thousands of Yazidi women and girls were sold to ISIS members as slaves when the fighters overran the Yazidi homeland in northern Iraq. The Yazidi people follow an ancient, non-Muslim religion that ISIS considers devil worship.

The judge charged Jennifer W. with murder and war crimes.

ISIS SLEEPER CELLS BURN, BLOW UP AND SLAUGHTER HUNDREDS IN UPTICK OF ATTACKS ACROSS IRAQ AND SYRIA

The German parliament has passed legislation that strips Germans with dual nationality of their citizenship if they join foreign terrorist militias. The law’s wording was deliberately left vague so that, while aimed at ISIS, it could be applied to other terrorist groups.

German government spokesperson Steve Alter said the government faces a big challenge in bringing the former ISIS fighters to justice. German law requires concrete proof of wrongdoing such as photos or social media accounts, which makes it difficult to bring charges. It is often impossible to gather such evidence because Germany does not have an embassy in Syria where Kurdish forces hold many of the fighters. German courts have had to drop cases for lack of evidence.

Frank Jensen, who writes about extremism for the center-right daily newspaper Der Tagesspiegel, told Fox News that according to the German Interior Minister, Horst Seehofer, each prisoner must be thoroughly investigated in Syria, or Iraq before they can be brought to trial in Germany.

“We have a huge danger from Islamic terror in Germany, and many people don’t want them to come back,” said Jensen, recalling the 2016 Muslim terrorist attack that killed 12 people at a Christmas market in Berlin.

“Some get aggressive suddenly and end up stabbing people,” he added, noting that many have been left with deep emotional scars from their exposure to combat and torture.

1,100-POUND US BOMB FROM WWII DEFUSED IN GERMANY AFTER MASS EVACUATION

The government is trying to rehabilitate them, he said, but it will take a long time to normalize their behavior.

“I don’t know whether the government is willing to accept a lengthy de-radicalization program," Jensen said.

ISIS is guilty of many crimes against humanity. For example, Khaled Al Asaad, the chief archaeologist in the ancient city of Palmyra in Syria, was beheaded for refusing to reveal the location of hidden artifacts. And young girls, who have been gang-raped, have disfigured themselves to avoid being repeatedly assaulted.

CLICK HERE TO GET THE FOX NEWS APP

Some in Germany are now speaking out for the victims.

“Justice should be served on all who participated in the ISIS state,” Berger said. “Including those who continue to propagate the deadly and inhumane philosophy of the movement in Germany and Europe.”