EU raids banks over claims of interest rate manipulation

European investigators have raided banks in London to seize financial documents as part of a widening investitgaion throughout Europe into alleged manipulation of interbank lending rates.

Royal Bank of Scotland received a visit from European Union officials early on Tuesday morning as part of an inquiry into companies active in derivatives linked to the Euribor, a key short-term reference rate for banks lending to each other in the EU money markets.

Deutsche Bank was also the subject of raids in London, while Barclays is expecting a visit, a source close to the situation said. All three banks declined to comment and the European Commission did not name those involved. The EC said: "The commission has concerns that the companies concerned may have violated EU antitrust rules that prohibit cartels and restrictive business practices."

A spokeswoman for the European Union competition commissioner, Joaquin Almunia, declined to say how many banks were involved or where the raids took place. Further raids are expected, however. "Inspections are always the first step," the spokeswoman added.

Euribor is set daily by 44 banks active in the eurozone interbank market. This week's raids follow year-long investigations by the US, Japan and Europe into alleged bank collusion during the financial crisis over the London interbank offered rate, Libor – the most widely used reference lending rate.