Six Minnesota men have been charged with plotting to go to Syria and help ISIS, federal authorities announced on Monday.
Four of the men were arrested on Sunday in Minneapolis and two in San Diego, said Andrew M. Luger, the top federal prosecutor in Minnesota. Authorities said there was no credible evidence that anyone in the United States was threatened.
The men were charged with conspiracy and trying to provide material support to a foreign terror group. Authorities said that they are friends, and are associates of three other Minnesota men who have been charged with similar crimes.
Related: State Department comments on arrests of ISIS supporters
"What this case shows is that the person radicalizing your son, your brother, your best friend may not be a stranger," Luger told reporters. "It may be their best friend right here in town."
Luger said the charges were the result of a 10-month investigation.
"We have a terror recruiting problem in Minnesota," he said.
The six arrested on Sunday are Zacharia Yusuf Abdurahman, 19; Abdurahman Yasin Daud, 21; Adnan Abdihamid Farah, 19; Mohamed Abdihamid Farah, 21; Hanad Mustafe Musse, 19; and Guled Ali Omar, 20.
Three of them were stopped in November while trying to board international flights at John F. Kennedy International Airport in New York, authorities said. A fourth was stopped in November trying to fly from Minneapolis to San Diego.
Members of the group, along with a seventh person whom the authorities identified as a confidential source, later tried to get fake passports, the prosecutor said.
Community workers have told NBC News that terrorist groups including ISIS, al-Qaeda and al-Shabab have been recruiting young men from Minnesota's Somali community, the largest in the country, for some time.
This story originally appeared on NBC News