ITV News Correspondent John Ray reports
Two British men who fled to Syria to fight alongside rebels today admitted preparing acts of terror.
Mohammed Nahin Ahmed and Yusuf Zubair Sarwar, both 22, from Birmingham, travelled to the war-torn country last May and were arrested at Heathrow Airport by anti-terror police on their return in January.
A trial due to start at Woolwich Crown Court was abandoned after both pleaded guilty to one count of engaging in conduct in preparation of terrorism acts, contrary to Section 5 of the Terrorism Act.
A date for sentencing is expected to be announced in the coming weeks.
West Midlands Police were told about the childhood friends' case after being contacted by Sarwar's parents.
His mother - who believed he was travelling to Turkey on a trip with Birmingham City University - realised her son's destination after she found a letter from him revealing he had fled to Syria to "do jihad".
In the hand-written note, he included money to pay off outstanding debts and instructions to end his mobile phone contract.
Traces of military grade explosives were found on their clothes and trainers, while officers discovered camera images showing them brandishing weapons in Syria.
Social media and email conversations between the pair and extremists were also found, as they sought advice from extremists in Sweden and Denmark.
The court also heard how the men had ordered books including Islam For Dummies, the Koran For Dummies and Arabic For Dummies as part of their preparation to fight in Syria.
After their arrest, the pair claimed they were travelling to Syria for humanitarian reasons.
But officers found "thousands" of images of the pair holding guns in the Syrian city of Aleppo.
Speaking after the guilty pleas, the judge said they "carefully planned a journey from the UK to Turkey and on to Syria to join Islamist rebels fighting the regime of Bashar al-Assad".
Assistant Chief Constable Marcus Beale encouraged parents who are concerned that a family member is considering travelling to Syria to get in touch.
"These young men went to considerable lengths to hide their plans from their families, who have since suffered a great deal of distress," he added.
"It's not easy to know everything that a family member is doing all of the time, but we encourage parents to hold a healthy interest and curiosity into who their children mix with and who seems to hold a strong influence over them.
"Crucially, if families are worried that a member is thinking of travelling to Syria it is very important that they tell the authorities as soon as possible."