A seventh man has been arrested in connection with a counter-terrorism operation in Birmingham, police said.
The 20-year-old, from Yardley, Birmingham, was detained at around 6pm on Thursday on suspicion of the commission, preparation or instigation of an act of terrorism in the UK, West Midlands Police said.
A spokesman said he was arrested at a police station which he had agreed to attend.
Six men arrested earlier in the week as part of the same operation remain in custody. Police have until Sunday night to charge or release them, or apply for a warrant of further detention.
The men, all from Birmingham and aged 25 to 32, were arrested on Sunday night and Monday morning as part of a major pre-planned counter-terrorism operation, following a joint investigation by police and MI5.
A seventh person, a 22-year-old woman from Saltley, who was arrested on suspicion of failing to disclose information contrary to the Terrorism Act 2000, was given bail pending further inquiries.
It is understood the investigation relates to suspected Islamist extremism, but it is not thought that an attack or threat was imminent.
A spokesman for the force previously said forensic teams had conducted searches at a total of 16 properties in the city.
The men, from areas of Birmingham including Moseley, Sparkbrook, Balsall Heath, Sparkhill, Yardley and Ward End, were detained at or near their homes.
West Midlands Police said the "large-scale operation" had been running for some time and had been subject to regular review, adding the action was necessary "in order to ensure public safety".