Japanese regulators are probing JPMorgan for its alleged role in a high-profile insider trading case, Dow Jones Newswires reported Wednesday, the latest bad news for the embattled US investment bank. The Securities and Exchange Surveillance Commission (SESC) recommended Tuesday that an asset manager be fined for short-selling Nippon Sheet Glass shares after illegally obtaining information ahead of a stock sale JPMorgan was underwriting. A sales executive for the US bank -- which is already reeling from a shock $2.0 billion loss on derivatives trading -- was the source of the leak, Dow Jones said, citing an unnamed source. The 2010 case is among several at the centre of a wide-ranging investigation by Japan\'s securities watchdog into insider trading. The SESC did not name the alleged source, but JPMorgan was the lead underwriter and one of just two taking part, according to Dow Jones, with the other, Daiwa Securities, already saying it was not involved in the inquiry. In a carefully worded statement, JPMorgan Securities Japan confirmed on Wednesday it was in talks with regulators, but added the firm \"has not received any indication from authorities that suggests JPMorgan\'s involvement either by the company as a whole, or by any department as a whole\". The statement, which made no reference to the possible involvement of an individual, added: \"We take this matter extremely seriously and will continue to take measures to enhance our internal control. \"We are cooperating fully with the authorities on this matter.\" The SESC declined to comment when asked if it was investigating the US bank over the insider trading allegations, saying the relevant spokesperson was unavailable. It recommended a fine of only 130,000 yen ($1,600) against the fund manager involved, Asuka Asset Management, even though the firm was alleged to have made more than 60 million yen. Token punishment levels are common in Japanese insider trading cases. On Tuesday, the SESC asked financial regulators to fine Sumitomo Mitsui Trust Bank about 80,000 yen over a separate alleged insider trading case connected to a share offering by Mizuho Financial Group. In March, the agency also recommended that Chuo Mitsui, now part of Sumitomo Mitsui Trust Bank, be fined 50,000 yen for insider trading of shares in energy firm Inpex Corp. Japan\'s biggest brokerage Nomura Holdings was an underwriter in both those cases, and has confirmed it is under investigation. \"We\'ll deal with this matter strictly based on the findings of the Commission\'s inspection and recommendations of a group of outside attorneys,\" Dow Jones quoted the brokerage as saying.