Five UK nationals arrested on suspicion of explosive and terrorism offenses following a major incident near RAF Fairford in Gloucestershire are to be released on police bail. The men, all in their 20s and from London, were detained after suspicious vehicles were reported near the airbase early Sunday morning.

Counter Terrorism Policing (CTP) is leading the investigation, exploring multiple lines of inquiry, including potential involvement of individuals acting on behalf of a foreign state. The operation was reportedly not intelligence-led, adding a layer of complexity to the ongoing probe.

Gloucestershire Police received a call at 00:45 BST on Sunday regarding three suspicious vehicles heading towards RAF Fairford. A subsequent police operation led to the arrest of the five men near Whelford. A bomb disposal team was deployed to examine vehicles within a 400-meter cordon, with aerial footage showing a robot near white vans in a wooded area.

Assistant Commissioner Laurence Taylor of CTP stated on Monday that the three vehicles had undergone extensive examination with support from military and forensic experts. The investigation aims to determine the full circumstances surrounding the incident and any potential threats.

RAF Fairford, located in the Cotswolds, has a history of use by the U.S. military, recently serving as a staging post for strikes on Iran. The U.S. military confirmed it is working closely with UK counterparts to monitor the situation and ensure the safety of personnel and the local community.

The five arrested men were initially detained under the Explosives Act before being further arrested on suspicion of preparation of a terrorist act. CTP has confirmed they are UK nationals aged between 23 and 25, all residing in London. They will be released on bail under stringent conditions.

While details remain under investigation, the incident has prompted significant police and counter-terrorism activity. The involvement of a bomb disposal unit and the establishment of a cordon underscore the seriousness with which the authorities are treating the matter.

Questions remain about the exact nature of the threat, the individuals' motivations, and the extent of any foreign state involvement, as counter-terrorism investigators continue their extensive work at the scene.