Federal authorities are looking to bring terror-related charges against one or more Somali-Americans from the Minneapolis area, and witnesses to the case have been subpoenaed to testify before a federal grand jury, according to a Muslim leader in the area and a woman who said she testified before the grand jury this morning.

For several months the FBI has been investigating about a dozen Somali-American men who disappeared from their homes in the Minneapolis area late last year and may have joined terrorist groups overseas. One of the men, 27-year-old Shirwa Ahmed, later blew himself up in Somalia. The FBI recently called him the first U.S. citizen to carry out a suicide bombing, and FBI Director Mueller said he was "radicalized in his hometown in Minnesota."

The FBI has interviewed at least 50 people in the Somali community and subpoenaed at least 10 people to testify before a grand jury in Minneapolis, according to Farhan Hurre, the director of the Abubakar As-Saddique Islamic Center in St. Paul, one of the largest mosques in the Twin Cities. He said most of those subpoenaed are students at the University of Minnesota. At least two of the men still missing were students at the University of Minnesota.

A woman who identified herself as a 20-year-old student at the University of Minnesota said she testified before the grand jury this morning, after receiving a subpoena on Friday. A copy of the subpoena obtained by Fox News says, "You are hereby commanded to appear and testify before the Grand Jury of the United States District Court." The subpoena told her to appear at 9 a.m. local time.

She said FBI agents previously told her that she has "some important information" related to an ongoing FBI investigation. The woman told Fox News she knew four of the Minneapolis-area men who went missing late last year, but she said they were only "acquaintances" whom she knew from growing up in the area.

The woman said that during her four-hour testimony today she was asked about the missing men, who they hung out with before they left, and why they may have left. She said the FBI informed her that she was not a target of the investigation and did not face any charges.

The woman also said she asked the FBI today what will happen to the missing men's families, and if the men will be allowed to return to the United States. She said the FBI refused to answer.

Hurre said he was told a case has been opened against at least one unidentified person. He said authorities are now "trying to bring the pieces together of what's going on here" in Minneapolis. Specifically, he said investigators are trying to determine who organized the missing group of men, who financed them and how were they recruited.

It's unclear whether any charges would target the missing men or someone outside of the group. A spokesman for the FBI Field Office in Minneapolis declined comment. Likewise, a spokesman with the Justice Department's National Security Division said he can't confirm or deny matters relating to a possible grand jury.

The Abubakar As-Saddique Islamic Center has received some unwanted attention, including threatening e-mails and phone calls, after it was revealed that Ahmed and some of the other missing men had ties to the mosque. In a statement posted online, the mosque says suggestions that it had any role in the disappearance of the Somali men are "unfair" and untrue.

"Abubakar Center didn't recruit, finance, or otherwise facilitate in any way, shape, or form the travel of those youth," the statement says.

Hurre said the media attention and subsequent backlash are "destroying our community."

Last month the mosque invited the FBI to meet with community and religious leaders to discuss the missing men and other issues affecting the Somali-American community in Minnesota. Hurre said the FBI called this morning to say they are now "ready to meet." A meeting between the FBI and the Abubakar As-Saddique Islamic Center is scheduled for Thursday. Hurre said it will be the first meeting between the FBI and the mosque since federal authorities launched their investigation.

At a forum in Washington two weeks ago, FBI Director Robert Mueller said the trend of young men "radicalized and recruited" in the United States to take up arms overseas "in particular concerns us."

"It raises the question of whether these young men will one day come home, and, if so, what they might undertake here," he said.

The U.S. Senate Committee on Homeland Security is set to hold a hearing tomorrow morning looking at Somalia-based terrorist groups, particularly the Al Qaeda-linked al-Shabaab, and their efforts to recruit inside the United States. A top-ranking official with the FBI's National Security Branch, J. Philip Mudd, and the Deputy Director for Intelligence at the National Counterterrorism Center, Andrew Liepman, are scheduled to testify at the hearing.