Police arrested three men who attempted to rob an online bank on Tuesday.
According to Egg PLC the arrests came after a six-month investigation in which the bank cooperated with the police to set up an electronic trap.
"We installed a piece of software that enabled us to identify these people," said Egg spokeswoman Poppy Nagra. "No customers lost money. There was no breach of security. It was very much a proactive security exercise for us."
Egg, the online banking offering from Prudential PLC, has 1.1 million customers.
It was the first case of its kind for Egg, Nagra said, and may well be the first such instance in the Internet banking industry.
Nagra said the men tried to get bank and credit-card loans. She said she couldn't elaborate further because the case is still being investigated.
The three men, all in their 30s, live in Buckinghamshire, Bedfordshire and Northamptonshire, British media reports said. They used a security loophole at Egg that allowed users to open multiple accounts using the same user information.
The three have been released on bail, reports said. Other Internet banks may have also been targeted.