U.S. officials said Wednesday that five Americans detained in Pakistan are believed to be the same five young men that vanished from Washington last month. One of the missing young men, officials said, left a farewell video saying Muslims must be defended and featuring images of American casualties.

Two officials did not identify which of the five missing students made the video. Pakistan authorities say they have detained five unidentified Americans as they investigate the case. The FBI has been looking for the men for more than a week.

The U.S. officials spoke on condition of anonymity because they were not authorized to discuss the investigation.

The FBI has been searching for the men since their families reported them missing and expressed fears they may have gone to Pakistan, according to the two U.S. officials. The two are familiar with the case and spoke on condition of anonymity because they were not authorized to discuss it publicly.

The men were picked up in a raid on a house in Sarghoda in the eastern province of Punjab, police officer Tahir Gujjar said, adding that three of the men are of Pakistani descent, one is of Egyptian descent and the other is of Yemeni heritage.

Regional police chief Mian Javed Islam told The Associated Press that the men were between the ages of 18 and 20 and had spent the past few days in the city, which is near an air base about 125 miles (200 kilometers) south of the capital, Islamabad.

"They are being questioned and it is premature to say whether they are involved in or planned any act of terror," Islam said.

In Washington, a spokeswoman for the FBI's local office said agents have been trying to help find the student-age 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 and declined to comment further.

Nadeem Kiani, a spokesman for the Pakistani Embassy in Washington, called their investigation "preliminary." Foreigners can be detained when caught in certain areas of Pakistan, he said.

"It about their presence. What is the purpose of their visit? What are their connections," Kiani said.

He said Pakistani police are leading the investigation but will consult with the FBI if necessary

One of the men was Ramy Zamzam, a dental student at Howard University, located in Washington, according to the U.S. officials. A Howard University spokesman confirmed Zamzam was a student there but declined further comment.

The officials said one of the group _ they did not say which one _ left behind what investigators believe was a farewell video message, in which he talks about defending Muslims and shows images of U.S. casualties.

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 on 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 safe havens in lawless tribal areas near the Afghan border.

Samirah Ali, the president of Howard University's Muslim Student Association, said the FBI contacted her last week about Zamzam. The FBI told her Zamzam had been missing for a week.

Ali said she's known Zamzam for three years, and she would have never suspected he would be involved in radical activities. She said she did not know Zamzam's friends outside of Howard.

"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."

Ali said she hasn't seen Zamzam as much since he started dental school this year. She said he was religious, but she did not believe he was a radical. She said he comes from a nice family and did not have a girlfriend.

____

Khan reported from Islamabad. Associated Press Writers Eileen Sullivan, Matt Apuzzo, and Pamela Hess contributed to this report.