ISLAMABAD, Pakistan — Five young Americans captured in Pakistan are under investigation for possible links to terrorism after their families found a disturbing farewell video the missing men left behind showing scenes of war and casualties and saying Muslims must be defended.
Frantic relatives and worried FBI agents have been searching for the five men for more than a week, since their disappearance in late November. The missing men, ranging in age from 19 to 25, have family roots in the northern Virginia and Washington, D.C., area.
One, Ramy Zamzan, is a dental student at Howard University. NBC News reported that the names of the others are Umar Farooq, Ahmed Abdullah, Waqar ul Hassan and Imam Hassan Yasir.
Two U.S. officials, speaking on condition of anonymity because they were not authorized to discuss the case, said the five are believed to be under arrest in Pakistan. NBC News' Robert Windrem reported that U.S. officials said the five had been headed for Afghanistan to fight U.S. forces.
On the heels of charges against a Chicago man accused of plotting international terrorism, the case is another worrisome sign that Americans can be recruited within the United States to enlist in terrorist networks.
Leaders of an Islamic American group said the families of the five men asked the FBI for help and were particularly disturbed to see the video message.
"One person appeared in that video and they made references to the ongoing conflict in the world, and that young Muslims have to do something," said Nihad Awad, of the Council on American-Islamic Relations, or CAIR.
"The video's about 11 minutes and it's like a farewell. And they did not specify what they would be doing. But just hearing and seeing videos similar on the Internet, it just made me uncomfortable," Awad said. The video has not been made public.
Before they left, they did not seem to have become militant, a local Muslim leader said.
"From all of our interviews, there was no sign they were outwardly radicalized," Imam Johari Abdul-Malik said.
There was no indication the men had prior training or capabilities to bring to the battlefield, an official told NBC News. The men had no previous criminal records before the Pakistani raid, NBC News reported.
In Pakistan, police officer Tahir Gujjar said the five Americans were picked up in a raid on a house on Sarghoda in the eastern province of Punjab. He did not identify them, but said three are of Pakistani descent, one is of Egyptian descent and the other has Yemeni heritage.
S.M. Imran Gardezi, press minister at the Pakistani Embassy in Washington, said the men "are under arrest in Pakistan. The investigation is to see whether they had any links to any extremist groups." No charges have been filed.
Pakistani regional police chief Mian Javed Islam told The Associated Press that the men spent the past few days in the city of Sarghoda, which is near an air base south of the capital, Islamabad.
U.S. Embassy spokesman Rick Snelsire said officials there were aware of the reported arrests, but could not confirm them.
Pakistan has many militant groups based in its territory and the U.S. has been pressing the government to crack down on extremism. Al-Qaida and Taliban militants are believed to be hiding in lawless tribal areas near the Afghan border.
In Washington, a spokeswoman for the FBI's local office said agents have been trying to help find the men.
"The FBI is working with the families and local law enforcement to investigate the missing students and is aware of the individuals arrested in Pakistan," said the spokeswoman, Katherine Schweit. "We are working with Pakistan authorities to determine their identities and the nature of their business there if indeed these are the students who had gone missing."
She said the investigation continues, declining to comment further.
Video: Five Americans arrested in Pakistan According to officials at CAIR, the five left the country at the end of November without telling their families.
After the young men left, at least one phoned his family still claiming to be in the United States, but the caller ID information suggested they were overseas.
The families, members of the local Muslim community, took their concerns to CAIR, which put them in touch with the FBI and got them a lawyer, the group said.
'Very nice guy'
A Howard University spokesman confirmed Zamzam was a student there but declined further comment.
Samirah Ali, president of Howard University's Muslim Student Association, said the FBI contacted her last week about Zamzam, and told her he had been missing for a week.
Ali said she's known Zamzam for three years and never suspected he would be involved in radical activities.
"He's a very nice guy, very cordial, very friendly," Ali said, adding that he has a bubbly personality. "It really caught me off guard."
NBC News’ Robert Windrem and Pete Williams contributed to this Associated Press report.
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