Sony Corp <6758.T> said on Monday that its U.S. optical disc drive operations are under investigation for possible violations of anti-trust regulations, and indicated that other regulators could follow suit.

Sony Optiarc America, which supplies a lineup of optical disc drives, including those for DVDs, CD-ROMs, CD-Rs and Blu-ray discs, has received a subpoena from the U.S. Department of Justice's antitrust division, a Sony spokesman said.

Other countries are also seeking information on the state of competition in optical disc drives, he said, declining to comment further on which countries and whether or not Sony was a subject of other probes.

Sony also declined comment on what products were under investigation and whether or not blu-ray was included in the investigation.

Shares in Sony were up 2.3 percent at 2,730 yen, outperforming a 1 percent rise in Tokyo's electrical machinery index.

(Reporting by Mayumi Negishi; Editing by Joseph Radford)

Electronics Sony