The street where the fourth suspect died

James Nicholson, 19, Anthony Bates, 18, of north London, and Nicholas Waters, of no fixed address, were remanded in custody at Blackfriars Crown Court.

They all pleaded guilty to one charge of attempted burglary at Tiffany & Co, in central London, in October.

The date for sentencing has not been fixed. The fourth man, who is not being named, died as he fled on a motorbike.

A car was driven into the front doors of the shop in the early house of 6 October.

A man then started to smash the damaged doors with a sledge hammer.

The raiders got into the shop but fled when they realised they had walked into a police trap.

One of the men was on a motorbike with a fourth suspect - the bike collided with a parked car in another street.

The Independent Police Complaints Commission is investigating the death of the fourth man.