San Diego(CNN) A group of six young Minnesota men conspired to sneak into Syria and join ISIS "by any means necessary," federal prosecutors said Monday.
The group of friends, ages 19 to 21, were arrested Sunday.
"What's remarkable about this case was that nothing stopped these defendants from plotting their goal," said U.S. Attorney Andrew M. Luger of the District of Minnesota.
"They were not confused young men. They were not easily influenced. These are focused men who are intent on joining a terrorist organization by any means possible."
Recruiting for the ISIS terrorist network is a particular problem in Minnesota's community of Somali immigrants.
"People often ask who is doing the recruiting and when will we catch the person responsible," Luger said. "But it is not that simple. In today's case, the answer is that this group of friends is recruiting each other. They're engaged in what we describe as peer-to-peer recruiting."
Zacharia Yusuf Abdurahman, 19; Adnan Farah, 19; Hanad Mustafe Musse, 19; and Guled Ali Omar, 20, were arrested in Minneapolis. Abdirahman Yasin Daud, 21, and Mohamed Abdihamid Farah, 21, were arrested in San Diego after driving there in hopes of crossing into Mexico, Luger said.
They plotted for 10 months, Luger said. "Even when their co-conspirators were caught and charged, they continued to seek new and creative ways to leave Minnesota to fight for a terror group."
Another friend, who was part of the group, changed his mind and became a cooperating witness for the FBI, even tape recording some meetings, Luger said.
The FBI investigation has previously netted Abdullahi Yusuf, who has pleaded guilty to conspiring to provide material support to ISIS, and Hamza Ahmed, who has been indicted on charges of conspiring and attempting to provide material support to ISIS and is now pending trial, according to the criminal complaint.
The complaint describes a man, identified only as "Nur," who has spent time in Syria and allegedly helped the six accused men.
All six of the men who were arrested appeared in federal court on Monday but did not enter pleas.
A detention hearing was scheduled for Wednesday for the men in custody in Minnesota and Friday for those in California.
Prosecutors will seek to have Farah and Daud moved to Minnesota for the case.