Lawyer Henry Clack sadly knows a lot about Nigerian criminal gangs.
Mr Clack, a solicitor at London-based commercial law firm HFW, has to deal with them when he is representing global shipping firms that have found themselves victims of cyber attacks.
"Of the cases which HFW have been involved in, the most common counterparties that we've encountered are Nigerian organised criminal organisations," he says.
"They have been responsible for perpetrating several high value 'man-in-the-middle' frauds in recent years."
This type of fraud involves a hacker being able to intercept the communication between two parties, such as emails. The criminal then impersonates both in order to try to steal sensitive information, such as log-in details or financial data, or even to take control of a company's computer system.
