How news works. The Americans briefed journalists with a story that they knew was false, but hoped would stick. It didn't.

Guardian yesterday:

How the rescue of British aid worker Linda Norgrove ended in tragedy

Captor detonated suicide vest as US special forces rescuers arrived at the mud-walled compound in eastern Afghanistan

Guardian today:

Aid worker Linda Norgrove may have been killed by US troops

British aid worker Linda Norgrove may have been killed by a grenade thrown by US troops trying to rescue her from Taliban kidnappers in Afghanistan, David Cameron said today.