A further arrest has been made in connection with two aircraft being damaged at an RAF base.
A 22-year-old man, of no fixed abode, was arrested on Friday in Bedford on suspicion of the commission, preparation or instigation of acts of terrorism, contrary to Section 41 of the Terrorism Act 2000, Counter Terrorism Policing South said.
Two Voyager planes were damaged at RAF Brize Norton, Oxfordshire, on June 20.
The arrested man is currently in police custody, police added.
The action, which was claimed by the group Palestine Action, caused £7 million worth of damage to the aircraft.
The Government moved to proscribe the group under anti-terror laws after the group claimed responsibility for the action.
Four people were charged last month in connection with the incident.
