Eight foreign nationals were arrested in recent days by U.S. Immigration and Customs Enforcement in the U.S., suspected of having ties to the terrorist group ISIS. A U.S. official with knowledge of the investigation confirmed this.

Eight individuals from New York City, Los Angeles and Philadelphia were arrested on immigration charges. The official stated that each Tajikistani entered the U.S. through the southern Mexico border. The officials said that they are still in U.S. custody.

Officials said that no information derogatory was found about the individuals at their border screening, but later the U.S. learned of information linking them to ISIS. The individuals do not currently face any charges related to terrorism.

The arrests by ICE were coordinated with the FBI Joint Terrorism Task Forces.

In a joint press release, the Department of Homeland Security (DHS) and FBI stated that “the individuals arrested are being held in ICE custody pending further removal proceedings.”

As the FBI and DHS recently explained in public bulletins and with partners, the U.S. is in a high-threat environment. The FBI and DHS continue to work around the clock, with our partners, to identify, investigate and disrupt any potential threats to national safety,” continued the statement.

The arrests were first reported by The New York Post.

After the March 22 ISIS attack on a Russian concert venue that left 145 dead, FBI Director Christopher Wray issued a warning in April about the possibility of “coordinated attacks” in the U.S.

Last week, President Joe Biden took an executive action that allows him to shut down the southern border for migrants when the situation becomes overwhelming. He has been repeatedly criticized by Republicans because of his handling of the surge of migrants.