British police have been given more time to question six men arrested in what officials called a significant counterterrorism operation.
The suspects, aged 25 to 32, were detained Monday in the central England city of Birmingham, on suspicion of "the commission, preparation or instigation" of a terrorist act.
Officials said the arrests related to Islamic extremism and were one of the year's most significant anti-terror operations.
Police said Tuesday they had been given until midnight Sunday to charge the men, release them or apply for a further extension.
Terrorist suspects can be held for up to 14 days before they must be charged or released.
A woman arrested on suspicion of failing to disclose information about terrorism has been released on bail.