In a company blog post Friday, Google confirmed reports that it is being investigated by the Federal Trade Commission, the latest in a string of run-ins Google has had with the FTC and other regulators over its business practices.

Google said that it received formal notification about the probe from the FTC on Thursday and that it does not know the subject of the investigation, though it seems likely the probe will look at the company’s search features.

Google already faces several antitrust investigations related to search. The company won approval in April from the Justice Department to acquire ITA, a travel search company. The Justice Department investigation before the ruling raised concerns that the deal would give Google control over too much search technology and may use that to cut out competitors.

In November, the European Commission launched a formal antitrust probe into Google’s business in December, after several smaller search engines — two associated with search competitor Microsoft — complained that Google was burying their search results. A complaint from German online mapping company Euro-Cities, which claims that free Google Maps integration destroys its business model, is also part of the investigation.

In the United States the Texas attorney general Greg Abbott was the first regulator to look into Google’s practices in September. In May, Oklahoma State Attorney General E. Scott Pruitt said he would be interested in joining other states and federal agencies’ probes into Google’s “dominance of the Internet search engine industry” and possible violations of consumer privacy laws.

California, New York and Ohio have reportedly begun investigations into the Google’s antitrust practices. Representatives from the offices of the attorneys general of California and Ohio declined to comment. The New York attorney general’s office could not immediately be reached for comment.

Google has also faced FTC probes into consumer privacy issues, but some have criticized the agency, saying that it has not been tough enough on the search company.

In October 2010, the FTC dropped an investigation into a privacy breach that occurred when the company’s Street View cars collected data from WiFi networks. At that time, the FTC said that the company did not put enough emphasis on privacy. Google appointed a privacy manager and pledged to broaden privacy training.

In March, the agency settled with Google over privacy concerns raised over the company’s roll-out of its social network, Buzz. The settlement marked the first time the FTC required a company to implement a comprehensive privacy program to protect consumers’ information, and the first time the FTC has alleged violations of the privacy requirements of the U.S.-EU Safe Harbor Framework. Google must also submit to an independent privacy audit every two years.