Former Guantanamo Bay detainee Moazzam Begg has pleaded not guilty to seven terror offences connected with the civil war in Syria.
The 45-year-old appeared via video link from prison to deny the charges.
Begg, of Hall Green, Birmingham, is accused of attending a terrorist training camp in Syria October 2012 and April 2013 and funding terrorism by providing a generator in July last year.
He also faces five counts of possessing an article for a purpose connecting to terrorism between December 31, 2012 and February 26 this year.
Begg will stand trial at the Old Bailey on October 6.
Police in the West Midlands have been given an extra five days to question three men and one woman arrested on suspicion of Syria-related terrorism offences.
They can now be detained until March 4th.
Those detained include Moazzam Begg, who is suspected of attending a terrorist training camp. He previously spent nearly three years in Guantanamo Bay detention facility before being released without charge.
They were arrested in the early hours of yesterday morning.
Campaign group CAGE says it is "outraged" by the arrest of Mozzam Begg and claim the arrest was linked to the group's pending report on Syria.
A statement reads: "This arrest forms a part of the general approach by the UK security agencies which considers any travel to Syria as suspicious.
"There has been a concerted campaign of harassment against Muslim individuals and charities who get involved in supporting the victims of the Syrian crisis.
"We do not accept involvement by Moazzam Begg in any form of terrorism. He is simply one of many individuals and charities involved in Syria being viewed with suspicion in an effort to send a message to the wider Muslim community that working in Syria is no go area for them...
"Moazzam has been very open about all of his travel and all of his objectives with regards to that travel including exposing British complicity in rendition and torture. CAGE challenges the timing of Moazzam's arrest given his travel to Syria took place in December 2012.
"CAGE is worried that the timing coincides with the planned release of our report on Syria and a major news piece that was due to be televised soon.
"We are also concerned that the Police and the security services are using the wide scope of terrorism laws, and applying them in Syria to set precedents that will make legitimate activity unlawful in future."
Neighbour Maureen Cooper reported seeing police activity at Moazzam Begg's house in Hall Green from about seven o'clock.
She said a number of unmarked vehicles had arrived, one of which appeared to contain photographic equipment.
A small silver car and a green people carrier were taken away on low loaders, she said.
She also said Mr. Begg's wife had told her in a conversation last autumn that he had been abroad for "several months."
"MI5 was concerned about the possibility of Britons in Syria being radicalised and returning to pose a potential threat to national security," he wrote in December 2013 on the website of his campaign group CagePrisoners.
"I told them that Britain had nothing to worry about, especially since British foreign policy, at the time, seemed in favour of the rebels. At the end of the meeting I was assured by MI5 that my proposed return to Syria to continue my work would not be hindered, and it wasn't."
He adds that on returning from a trip to South Africa in December he was "met upon arrival at Heathrow by officials who served me with a notice to seize my passport under the 'Royal Prerogative' stating that it was assessed my previous visits to Syria had constituted involvement in terrorism."
A West Midlands Police spokeswoman said:
She added that naming Mr Begg does "not imply any guilt".
Head of investigations for West Midlands Counter Terrorism Unit, Detective Superintendent Shaun Edwards, said earlier:
Birmingham-born Moazzam Begg was arrested in Pakistan in 2002 on suspicion of links to the al-Qaeda terrorist network and moved to Afghanistan and then Guantanamo Bay in Cuba in 2003.
He was released without charge in 2005 and went on to speak in US and UK universities about his time in the US-run detention camp.
He was one of a number of former detainees to file a lawsuit against the British government and eventually reached an out-of-court settlement.
He has since founded a charity which lobbies for the rights of terror suspects.
West Midlands Police raided the home of former Guantanamo detainee Moazzam Begg at approximately 6am this morning, and he was arrested on suspicion of Syria-related terrorism offences.
Police are now searching his home, and have erected a tent in his garden as part of their enquirers.
ITV News can confirm that former Guantanamo detainee Moazzam Begg has been arrested by West Midlands Police on suspicion of Syria-related terrorism offences.