There is little confirmed information about how organs are harvested, but doctors have given accounts of driving to execution grounds with specially equipped ambulances carrying nurses and containers for the organs. The body is picked up, carried to the ambulance and brought to a hospital where the organs are stripped. Executions on the mainland are generally carried out by a bullet to the back of the head, or in the heart. However, the introduction of the lethal injection in the past decade means more organs are left intact. Almost all organs harvested from dead bodies in China come from executed prisoners, raising questions about how organs are obtained and how they are supplied to the patients who need them. China only admitted recently that the organs of executed prisoners were sold to foreigners, such as rich Japanese, for transplant. Huang Jiefu , deputy health minister, told Caijing magazine that the government was keen to standardise the management of the supply of organs from executed prisoners. A key issue, despite new legislation, is how much control prisoners have over whether to donate their organs. The central government said all condemned prisoners who agreed to donate their organs after their deaths do so of their own will, and in some cases their families are paid. Some human rights organisations accuse authorities in China of scheduling executions to coincide with transplant operations, and some families have sued the authorities for using the organs of executed relatives without consent.