The FBI is investigating the arrest in Pakistan of five reported US men on suspicion of extremist links.

FBI介入调查五名美国人涉嫌与极端分子联系而被巴基斯坦当局逮捕一案。

The FBI is probing if the men are those missing from Virginia

The men were arrested in a raid突袭，搜捕 on a house in Sarghoda in eastern Punjab province, Pakistan's US embassy told the BBC.

The FBI said it was trying to determine whether they are the same men who were reported missing from their homes in the US state of Virginia last month.

The US State Department said it was also seeking information on the men.

Three of them are reported to be of Pakistani descent, one of Egyptian heritage遗产，传统 and the other of a Yemeni background.

'Video message'

"If they are American citizens, we of course are going to be very interested in the charges that they've been detained扣留 on and in what sort of circumstances they're being held," said spokesman Ian Kelly.

FBI spokeswoman Katherine Schweit said the agency was aware of the arrests and was in contact with the families of the missing students.

"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 Pakistani embassy in Washington said the men were arrested in a house belonging to an uncle of one of them.

He said the house was already of interest to local police and that no charges had yet been filed against the arrested men.

Secretary of State Hillary Clinton declined to拒绝 comment on the arrests, reported the Reuters news agency, but said the US had to "work more closely with both Afghanistan and Pakistan to try to root out根除，发现 the infrastructure¹基础设施 of terrorism that continues to recruit招募 and train people".

The five students were reported missing from their homes in northern Virginia by their families in late November.

The families reportedly passed on a video to members of the US Council on American-Islamic Relations (CAIR).

Nihad Awad, the leader of CAIR, said the video appeared to be "like a farewell".

"One person appeared in that video and they made references to提到，谈及 the ongoing前进的，进行的 conflict in the world, and that young Muslims have to do something," Mr Awad told Associated Press news agency.

He said the video had made him "uncomfortable" and he advised the men's families to contact the FBI.