Up to 20 Western hostages are being held by the jihadi group that beheaded James Foley.
As well as the journalist Steven Sotloff, who was threatened with beheading by the same man who murdered Foley, Islamic State in Iraq and the Levant (Isil) is holding a number of aid workers, thought to include Vanessa Marzullo, 21, and Greta Ramelli, 20, both Italian.
Three aid workers employed by the International Committee of the Red Cross (ICRC) are also being held hostage after they were abducted last October.
As fears grew that Isil could make good on its threat to murder more hostages, families of those being held defended their loved ones’ decisions to travel to Syria.
Ms Ramelli’s mother, Antonella, said her daughter had been determined from an early age to look after others, starting by helping out in a retirement home when she was 12.
Responding to suggestions that she should not have allowed her daughter to travel to Syria, Mrs Ramelli said: “When you hear your daughter say ‘Mamma, in that country they are killing children, I must go and help,’ what can you say?”