A UK investigation into potential manipulation of currency markets is looking at a former trader at Royal Bank of Scotland who participated in electronic chat sessions with traders at other banks, according to people familiar with the investigation.

Richard Usher, currently JP Morgan's London-based head of spot trading for Group of 10 currencies in the region covering Europe, the Middle East and Africa, took part in the chat sessions with top traders from various financial institutions when he was an employee of RBS, these people said. The group of traders in the chat rooms was known by various monikers including "The Bandits' Club," and "The Cartel," the people said.