Mob Ties at Chinese Casinos Owned by US Firms? A new web site that loosely fashions itself after the now famous WikiLeaks sites is working to shed light on the increasingly profitable operations of American-owned casinos on the Chinese island of Macau, and is prodding gaming investigators to also take a closer look. The web site, Casinoleaks-macau.com, says it has relied on reams of publicly available financial documents to trace what it alleges are possible ties between the violent Chinese criminal underworld and well known American firms, including the Las Vegas Sands Corporation, which is run by the billionaire backer of Republican Newt Gingrich, Sheldon Adelson. "We believe that the issues we raise are urgent public policy concerns that cannot be ignored given the huge sums of money involved and the danger that criminal involvement in gaming poses for the people of the United States," wrote Jeffrey Fiedler, who helped launch the web site with the backing of the International Union of Operating Engineers (IUOE). Fiedler, who is the union's director of special projects, relayed his concerns in a letter sent today to the Nevada Gaming Commission and the Nevada Gaming Control Board -- agencies that police the gambling industry and aim to keep the industry free from the influence of organized crime figures. One of the American-owned casinos operating in Macau, MGM Grand, told ABC News that it considered the allegations outlined on the web site "baseless." "The concerns raised by the IUOE are baseless and reflect a complete lack of understanding of MGM's extremely robust policies and procedures for evaluating the suitability of its gaming room operators in Macau," said Gordon Absher, a spokesman for MGM Resorts International. The scrutiny comes at an unusually sensitive time for one of the largest gambling operators -- Las Vegas Sands Corporation. Adelson and his relatives have donated more than $10 million to Gingrich. And the gaming mogul has signaled he could spend as much as $100 million to try and influence the outcome of the 2012 presidential election. ABC News reported in January that Las Vegas Sands has for more than a year been under criminal investigation by the Department of Justice and the Securities Exchange Commission for alleged bribery of foreign officials, according to corporate documents. And in a civil law suit, a former company executive has alleged the casino has had "involvement with Chinese organized crime groups, known as Triads, connected to the junket business." The triads -- Chinese organized crime syndicates â have allegedly had ties to the outfits organizing high stakes gambling junkets for wealthy Chinese travelers. Sands corporate spokesman Ron Reese has not responded to phone messages left Wednesday. In January, he directed ABC News to earlier statements that Adelson has made refuting the allegations and dismissing the investigation. At a gaming forum last year, Adelson said the lawsuit "is not a serious case" and that the federal investigations would find no wrongdoing. When the smoke clears, I am 1,000 percent positive that there won't be any fire below it. Adelson also said the federal case is built on a "foundation of lies." CasinoLeaks-Macau.com The recently launched website provides painstaking detail about the tangled web of corporate and private ownership of government licenses to operate VIP gambling rooms inside massive casino complexes on the Chinese island. The concessions allow the license holders to run junkets for mainland Chinese gamblers to special high-roller rooms set up inside casinos -- even those owned by well-known American gaming titans such as MGM Grand, Wynn Resorts and Las Vegas Sands. The junkets are responsible for organizing tours for Chinese gamblers, overseeing the gambling rooms â where the game of choice is almost always baccarat â and later collecting debts owed by the gamblers, who are often restricted in how much cash they can carry with them from mainland China to Macau. The CasinoLeaks-Macau.com website presents evidence that it says suggests that some of these junkets have been infiltrated by organized crime figures. And the website alleges that some of those criminal figures could be operating inside American-owned casinos. In his letter to Nevada gaming officials, Fiedler specifically references something called Neptune group, which he alleges has a "deep and continuing relationship" with a notorious Chinese gang leader. "We urge you to undertake a thorough investigation into the operation of the Neptune Group and its affiliated organizations to determine their suitability to do business with licensed casino operators in Nevada who also do significant business in Macau," Fiedler wrote. A spokesman for the Hong Kong-based Neptune Group has not responded to an email seeking comment. Mark A. Lipparelli, the chairman of the Nevada Gaming Control Board, could not be reached for comment Wednesday. Absher, the spokesman for MGM Resorts International spokesman, said his company has been proactive in working to root out criminal elements from its Macau property. He said an independent compliance committee, made up of former high-level law enforcement officials, has investigated and vetted the vendors who operate VIP rooms at the company's 35-story, 600-room resort in Macau. "This comprehensive review process found no evidence of any activity on the part of MGM's gaming room operators that is a cause for concern," Absher said. If any such activities were found, MGM would immediately terminate our contract with the operator. A spokesman for Wynn Resorts, reached Wednesday, said he had not seen the union's claims but would review them. The International Union of Operating Engineers is the 10th largest union in the AFL-CIO and has emerged as a watchdog for casino companies, including some that employ the union's members.