NEW YORK - The US Justice Department Wednesday charged two former senior UBS traders with manipulating the benchmark London Interbank Offered Rate (LIBOR).

UBS, the largest bank in Switzerland, earlier agreed to pay a total of $1.5 billion to US, British and Swiss regulators to resolve investigations of manipulating the LIBOR and other benchmark interest rates.

US Attorney General Eric Holder announces enforcement actions against UBS Securities Japan Co. Ltd. investment bank at the Justice Department in Washington Dec 19, 2012. [Photo/Agencies]

The two former UBS traders, named Tom Alexander William Hayes and Roger Darin, were both charged with conspiracy in a criminal complaint disclosed in Manhattan federal court on Wednesday, and they are the first traders to be criminally charged in the case.

Hayes is also charged with wire fraud, and a price fixing violation arising from his collusive activity with another bank to manipulate LIBOR.

According to probes conducted by the regulators, dozens of UBS staff engaged in efforts to manipulate the LIBOR, which is used to price trillions of dollars of funds, to benefit trading positions during the financial crisis.

Certain UBS employees also colluded with employees at other banks and cash brokers to influence benchmark rates, including the LIBOR, Yen LIBOR and Euro LIBOR, to benefit their trading positions from 2006 to 2009.

UBS will pay $1.2 billion to US Commodity Futures Trading Commission and the US Department of Justice, 160 million pounds ($260 million) to UK Financial Services Authority (FSA) and 59 million Swiss Franc ($65 million) to Swiss Financial Market Supervisory Authority (FINMA).

According to the bank's statement, its Japan's unit would enter a plea to one count of wire fraud relating to the manipulation of certain benchmark interest rates, including the Yen LIBOR.

Regulators in multiple counties have launched investigations against several world-leading banks for rigging benchmark rates to gain profits during the financial crisis.

The British banking giant Barclays paid 290 million pounds ($453 million) to settle LIBOR probes in the US and Britain in June.