California's attorney general is investigating Sutter Health and several other California hospital chains to see whether consolidation between hospitals and physician groups is illegally inflating health care prices, the Wall Street Journal reported Friday.

Attorney General Kamala Harris has issued subpoenas to Sutter, Dignity Health of San Francisco and several hospital chains in Southern California, the newspaper reported.

The Journal, quoting anonymous sources, said Harris has also issued subpoenas to California insurance companies.

Lynda Gledhill, Harris' press secretary, declined to comment when contacted by The Sacramento Bee Friday.

Kami Lloyd, a spokeswoman for Sutter, had no immediate information on the report. A spokesman for Dignity wasn't immediately available for comment.

Harris' probe began several months ago and is focusing on organizations that control hospitals as well as doctors groups. according to the Journal.