A published report says federal regulators are preparing to issue subpoenas to Google and other companies as authorities gather information for a broad antitrust probe into the Internet search leader's business practices.

The Wall Street Journal reported Thursday that the Federal Trade Commission will issue subpoenas "within days," which would signal that it has opened a formal investigation.

The FTC is looking into whether Google abuses its dominance of Internet search to extend its influence into other lucrative online markets, such as mapping, comparison shopping and travel. Rivals complain that Google Inc., which handles two out of every three Internet searches in the U.S., manipulates its results to steer users to its own sites and services and bury links to competitors.

Google and the Federal Trade Commission refused to comment Thursday.

The European Commission and the Texas attorney general have already opened investigations into whether Google uses its enormous clout as a major gateway to the Internet to stifle competition online. The EU launched its investigation after competitors -- U.K.-based price comparison site Foundem, French legal search engine ejustice.fr and Microsoft-owned shopping site Ciao -- complained that their services were being buried in Google search results.