LONDON — British prosecutors have filed eight fraud charges against a former UBS trader in the first criminal case in London in connection with the manipulation of benchmark global rates.

The case against the trader, Tom Hayes, comes after U.S. charges brought against him and a fellow trader late last year. UBS is one of more than a dozen global banks that have been ensnared in a multiyear investigation by United States, British and other authorities into manipulation of the London interbank offered rate, or Libor. Such benchmark rates help determine the borrowing rates for trillions of dollars of mortgages, business loans, credit cards and other financial products.

With the latest criminal charges, Britain has now escalated its part in the global crackdown on rate-rigging. The Serious Fraud Office of Britain said Tuesday that Hayes had been charged that morning with offenses of conspiracy to defraud in connection with the continuing Libor investigation.