The husband of Iraqi aid worker Margaret Hassan has said she may have been killed by her kidnappers, citing video tape evidence. Tahseen Hassan said: "I have been told that there is a video of Margaret which appears to show her murder. The video may be genuine but I do not know." Mrs Hassan's sisters said in a statement: "Our hearts are broken. We have kept hoping for as long as we could, but we now have to accept that Margaret has probably gone and at last her suffering has ended. "Our prayers and thoughts are with our dear brother-in-law Tahseen." The British Embassy in Baghdad has reportedly confirmed that the video showed her death. Care International said they were "shocked" to hear of Mrs Hassan's death and that the whole organisation was in mourning. It said: "It is with profound sadness that we have learnt of the existence of a video in which it appears that our colleague Margaret Hassan has been killed. "We are shocked and appalled that this has been the apparent outcome of her abduction. We want to express our deepest sympathy to Mrs Hassan's husband Tahseen, and to her family. "Mrs Hassan was an extraordinary woman who dedicated her life to the poor and disadvantaged in Iraq, particularly the children. The whole of Care is in mourning. "Through her courage, tenacity and commitment, Mrs Hassan assisted more than 17 million Iraqis living in the most difficult of circumstances. Everyone who met her was touched by her personality and compassion. "Care sincerely thanks the Iraqi people for everything they did to try to secure the safe return of Margaret Hassan and for the many expressions of support."