China's Foreign Ministry said on Monday that Chenyue Mao, the Wells Fargo banker who has been blocked from leaving the country, was involved in a criminal case and obliged to cooperate with the investigation.

A Wells Fargo banker has been blocked from leaving China due to a criminal matter, the country's foreign ministry has confirmed.

An Atlanta-based banker working for Wells Fargo has been prevented from leaving China, the latest incident that threatens to amplify concerns among Western executives about the potential consequences of visiting the world’s second-biggest economy.