Police in northern England have arrested three men who were trying to join an aid convoy leaving for the Gaza Strip.
They also seized three vehicles, which were due to form part of the convoy of 100 vehicles.
Lancashire police have not said what the detained men are suspected of doing.
The convoy, which was organised by the charity Viva Palestina, left London on Saturday.
Volunteers intend to drive 8,000km through France, Spain, Morocco, Algeria, Tunisia, Libya and Egypt where they hope to cross the border at Rafah into Gaza on 2 March.
Viva Palestina says the vehicles carrying food, toys and medicine.
Police said the cargo from the three seized vehicles was being "thoroughly checked."