The men were arrested on the M65
Three men arrested by counter-terrorism officers as they travelled to join a Gaza aid convoy have been released without charge.
Two vans and an ambulance were travelling to London when they were stopped on the M65 near Preston, Lancashire, on Friday.
The vehicles were released to continue their journey earlier this week.
Three men, aged 26, 29 and 36, were released without charge after extended questioning by officers.
They were among nine arrested - the other six were released at the weekend.
Several homes in Burnley were searched as part of what police said was an "intelligence-led operation".
Lancashire's Assistant Chief Constable Andy Cooke, said: "Lancashire Constabulary, with the support of the North West Counter Terrorism Branch, will robustly investigate any information that is passed to us about possible terrorist activity and if necessary take action.
"Terrorism affects us all and protecting the safety of the public is of paramount importance. Security for our communities is our highest priority and sometimes we have to make arrests.
"We will continue to do our utmost to help people recognise signs of suspicious behaviour so that they, in turn, can help defeat terrorism."
The convoy carrying medicine, clothing and shoeboxes of toys set off from London on Saturday accompanied by Respect party MP George Galloway.