Pennsylvania Attorney General Kathleen G. Kane said her office will join the Federal Trade Commission in a bid to block the proposed merger of Penn State Hershey Medical Center and PinnacleHealth System.

Combined, the two systems would control 64 percent of the market in the Harrisburg region, including Dauphin, Cumberland, Perry and Lebanon Counties, Kane's office said.

An FTC complaint to be filed Wednesday in U.S. District Court for the Middle District of Pennsylvania alleges that the two systems "compete vigorously on price, quality of care, and services provided, both for inclusion in commercial health plan networks and to attract patients from one another," according to Kane.

Eliminating that competition would lead to higher prices for consumers, she said.

Pinnacle has three hospitals, two in Harrisburg, where it is based, and one in Mechanicsburg.

Pinnacle and Penn State Hershey said in a joint statement that they were disappointed by the FTC action and "would carefully examine our options in continuing to advocate for our partnership."