British authorities Tuesday charged a former trader with conspiracy in connection with alleged manipulation of the benchmark London Interbank Offered Rate (LIBOR).

The UK Serious Fraud Office (SFO) says that Tom Hayes, 33, a former trader at UBS and Citigroup, has been charged with “offences of conspiracy to defraud” for his role in the alleged manipulation of LIBOR.

Hayes was one of three men who were arrested and interviewed by officers from the SFO and City of London Police back in December 2012. The three men were later released on bail. But this morning, Hayes was charged by London police with eight counts of fraud. The allegations have not been proven. He is to appear in court at a later date.

The SFO says that its investigation into the manipulation of LIBOR, which began in July 2012, is continuing.

Regulators in the United Kingdom and the United States have already sanctioned a couple of firms for their role in alleged LIBOR manipulation that was aimed at either signalling their own creditworthiness, or benefiting their trading positions.

Last year, UBS agreed to pay 1.4 billion Swiss francs (about $1.5 billion) to settle allegations from authorities in the U.S., UK and Switzerland.