The cause of death of a terminally ill cancer sufferer in France found dead in her flat days after being denied active euthanasia remains unknown. 52 year old Chantal Sebire, who suffered from a rare, incurable and painful form of cancer which left her disfigured, had been refused permission for an assisted suicide by a court on Monday.

Her death has re-ignited a public debate in France and further afield on euthanasia, which is legal in three EU countries out of 27. Under existing law, doctors said she could have been heavily sedated, fallen into a coma and died.

But Sebire, who is opposed to both artificial coma and suicide, wanted to set a legal precedent to allow euthanasia in exceptional cases. The government has pledged to consider revising a 2005 law known as "passive euthanasia".

Opponents of active euthanasia, including the Roman Catholic Church, say the sanctity of life overrides all other factors. Other critics fear a right to kill patients could easily be abused.