Ruth Akinyemi, 22, from Enfield, allegedly passed on personal details enabling criminals to contact Barclays Bank posing as the account holder.

All but one of the targeted customers lived in Camden and Islington.

Miss Akinyemi and Allen Strong, 30, from Croydon, south London, both deny conspiracy to steal.

Criminal property

The fraud was said to have taken place between July 2004 and April 2005.

Mr Strong is said to have used the information from Ms Akinyemi to siphon money into his own bank account.

He denies charges of acquiring criminal property and converting criminal property in relation to �14,500. The jury heard that another man, Thomas Sessazi, has admitted similar charges relating to �11,895.

One of the victims - Dr Susan Raymond, from Epping, Essex - lost �397,000, of which only �15,000 has been recovered, while another victim had �99,000 taken from their account.

Bank investigation

All targeted customers had their losses paid back by the bank, Mr Bennett said.

"This case demonstrates, at a time when identity theft is high on everyone's agendas, just how alarmingly simple it is to steal an enormous amount of money if you manage to get people's personal banking details," he said.

Miss Akinyemi was just 17 when she began to provide customer account details to people outside the bank, the court heard.

She was suspended from her job in Enfield in July 2004 but reinstated after a bank investigation found she had not done anything wrong. She was later transferred to St Albans, where the fraud allegedly continued.