LG.Philips and Samsung Electronics are being investigated by fair trade watchdogs in South Korea, Japan and the U.S. for possible price-fixing, a news agency report said.
The report, from South Korea's Yonhap news agency, follows a disclosure by LG.Philips on Monday that it was the target of an investigation by the Korean Fair Trade Commission, the Japanese Fair Trade Commission and had received a subpoena from the U.S. Department of Justice.
Shares of the flat screen maker hit a record low in Seoul on Tuesday. LG.Philips, a joint venture between LG Electronics and Philips Electronics, vowed to fully cooperate with authorities.
Yonhap cited unnamed regulatory and industry sources in reporting local antitrust authorities were also looking into possible collusion by Samsung and LG.Philips to fix the prices of LCD products and control their supply.
There were mixed reports from different spokesmen for the Korean commission. Reuters says calls to Samsung Electronics were not immediately returned.
LG.Philips was the world's biggest maker of the large LCD panels used in flat-screen TVs and PC monitors last year. But in 2006, the loss-making company has been overtaken by rival Samsung, which teamed up with Japan's Sony.