I read this on the BBC News website:
‘Special bullets’ killed Menezes
Specialised bullets designed to kill instantly were used by the police marksmen who shot dead Jean Charles de Menezes, the Old Bailey has heard.The bullets “immediately incapacitate” the victim and flatten, rather than pass through the other side of a body, the jury was told.
Of course these are simply hollow point bullets. The same type of bullet millions around the world use for hunting, self defense, policing and plinking every day.
The media just cannot get it right.
“The bullet flattens on impact and immediately incapacitates the target,” he told the court.
The British army invented JHPs (Jacked Hollow Points)
The hollow-point bullet, and the soft-nosed bullet, are sometimes also referred to as the dum-dum, so named after the British arsenal at Dum-Dum, near Calcutta, India, where it is said that jacketed, expanding bullets were first developed.
(From Wikipedia)
If you really want you can read the BBC article here.