Canada's Competition Bureau said in a court filing in Ottawa that a bank it did not identify has told the agency's investigators that people involved "were able to move" interest rates, the paper said.

The "cooperating party" is Swiss bank UBS AG (UBSN.VX), the WSJ said, citing people familiar with the situation.

"We don't comment on media speculation," UBS spokesman Peter McKillop told Reuters.

UBS has said earlier that it has been granted some immunity by Switzerland's antitrust authority in return for cooperating with its probe into the potential manipulation of the London Interbank Offered Rate, or Libor.

No banks or individuals have yet been charged with wrongdoing, the paper said.

Lawyers acting for the "cooperating bank" told the regulator that traders at six banks on the yen Libor panel -- Citigroup (C.N), Deutsche Bank (DBKGn.DE), HSBC Holdings (HSBA.L), JPMorgan Chase (JPM.N), Royal Bank of Scotland (RBS.L) and UBS -- influenced the rates, the Journal said, citing court documents.

Spokespeople for Citigroup, JPMorgan and Royal Bank of Scotland declined to comment to Reuters on the Journal report.

Deutsche Bank and HSBC Holdings could not immediately be reached for comment by Reuters outside regular business hours.

MODUS OPERANDI

The traders used emails and instant messages to tell each other whether they wanted "to see a higher or lower yen LIBOR (rate) to aid their trading position(s)," the paper said, citing a court filing.

They then "entered into agreements to submit artificially high or artificially low" quotes, according to the court documents," the WSJ said, citing court documents.

However, "not all attempts to affect LIBOR submissions were successful," it added.

The Competition Bureau said late on Monday that is investigating certain financial firms as part of a widening global probe into how banks set key interbank lending rates [ID:nL4E8DF16J].

Canadian regulator said it is investigating whether the traders also "conspired" with individuals at interdealer broker firms, the paper said, citing court documents.

Two London-based interdealer brokers ICAP PLC (IAP.L) and RP Martin Holdings Ltd are under investigation, the Canadian regulator said in the court documents, according to the paper.

Representatives of ICAP and RP Martin declined to comment to the WSJ, the paper said. They could not be reached outside business hours by Reuters.

Regulators since late 2010 have been investigating banks that help set interbank lending rates known as LIBOR and TIBOR in London and Tokyo, which are used to set interest rates on hundreds of trillions of dollars of securities.

More than a dozen traders and brokers in London and Asia have been fired, suspended or put on leave as part of the probe, the Financial Times reported last week.

(Reporting by Sakthi Prasad; additional reporting by Sruthi Ramakrishnan; Editing by Ramya Venugopal)

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