An Islamic State militant was arrested in Sweden this week but is now being held by immigration authorities because he has already applied for asylum, officials said Thursday.

The 46-year-old Bosnian jihadist who arrived at the country’s Malmo Airport Monday along with his four children, displayed signs of nervousness prompting Swedish authorities to delve deeper into the man’s identity, Swedish newspaper Sydsvenskan reported.

According to the paper, Swedish border police discovered that he had been flagged by French authorities and listed in the Schengen Information System (SIS), a governmental database employed by European countries to share information on individuals who pose a national security threat.

The unnamed jihadist is suspected of fighting with the Islamic State group in Syria and running a recruitment program for ISIS in Bosnia. He was arrested by Bosnian authorities in 2010 for possession of illegal weapons and spreading jihadist propaganda.

In February of this year he was arrested by Turkish authorities on suspicion of having traveled to Syria and was sent back to Bosnia where police confiscated his passport.

When he arrived in Sweden he was in possession of a new Bosnian passport.

The arrest comes as CIA Director John Brennan issued a stark warning in Congress Thursday, saying ISIS is working to send their operatives to the West.

“ISIL has a large cadre of Western fighters who could potentially serve as operatives for attacks in the West,” Brennan said.

“And the group is probably exploring a variety of means for infiltrating operatives into the West, including refugee flows, smuggling routes and legitimate methods of travel,” he added.

The man’s wife, who was already in Sweden visiting with friends, later came to pick up their four children.

At this time, the man remains in the custody of immigration services who must now handle his case. His asylum application prevents authorities from deporting him.

“As soon as people throw out the ‘asylum trump card’ the gates of heaven are opened for them,” police commissioner Leif Fransson said.

A spokesman for Sweden’s immigration authority said the country will act swiftly on the case as Bosnia is not considered a dangerous country.

“Everyone has a right to seek asylum according to Geneva Convention,” migration office spokesman Fredrik Bengtsson said.