The men, aged 30 and 22, were arrested on Wednesday morning on the University of Nottingham campus.

A spokesman for Nottinghamshire Police said that a district judge sitting at the City of Westminster Magistrates' Court in London had granted officers more time to question the men.

He said: "Nottinghamshire Police has been granted an extension to detain two men arrested under the Terrorism Act on Wednesday morning. A district judge from the City of Westminster Magistrates' Court extended the detention period to Tuesday, May 20. Officers are continuing to search premises in Nottingham.

"Nottinghamshire Police continue to work with community representatives, staff and students at the University of Nottingham to offer support and reassurance."

Police said the arrests were "low-key" and did not involve firearms officers.

It is understood police spent Friday examining computers seized after the two men, believed to be a student and a former student at the university, were arrested by officers from the Midlands Counter-terrorist Unit and Notts Police.

As part of their investigations, officers have searched premises at the university and properties in Nottingham.

A spokeswoman for the university said: "The university has been co-operating fully from the outset but the investigation is ongoing, and while police officers are undertaking their enquiries it would not be appropriate to comment in detail.

"Nottinghamshire Police has stressed that there is no risk to the university community or to the wider public. We accept that this sort of police operation is necessary and reasonable for the welfare of communities."