No one has claimed responsibility for the brutal attack, which happened in a largely residential neighbourhood. Those killed and injured were overwhelmingly civilians.

Doctors and nurses at Mirwais regional hospital – supported by an ICRC expatriate medical team including a surgeon and an anaesthetist – worked through the night to treat the casualties. The team is still operating on patients today.

Over 40 dead and more than 60 injured persons were brought to the hospital during the first few hours after the explosion.

The final tally of dead and injured is likely to be higher. "We are only seeing the casualties brought to Mirwais hospital," said Karl Mattli, head of the ICRC's sub-delegation in Kandahar.

ICRC water engineer Abdul Wadood, 48 years old, was at home alone when the blast occurred and died when the ceiling of the room he was in collapsed. His wife and 10 children were not in Kandahar at the time.

The ICRC is deeply shocked by the death of a much-loved colleague, and extends its deepest sympathy to Mr Wadood's family.

Under international humanitarian law – and as a matter of basic humanity – everything possible must be done to keep civilians safe from harm during conflict and other violence. Women, children, the elderly and the infirm are especially vulnerable and must be spared at all times. Last night's blast is yet another indication of the suffering that civilians all over Afghanistan have to endure.