WASHINGTON (AP) — The United States is urging the Persian Gulf kingdom of Bahrain to ensure that a prominent political opponent is treated properly amid reports of a hunger strike.

State Department spokesman Edgar Vasquez says the U.S. is aware of the reports about Bahraini prisoner Abdul Jalil al-Singace, who has been held since 2011. Al-Singace's protest concerns prison conditions.

Vasquez says the U.S. wants Bahrain to "ensure that all prisoners have access to adequate medical care, and to investigate all reports of mistreatment of prisoners."

Washington has chided the Sunni-led government for the treatment of its Shiite majority. But it has also regularly reaffirmed the countries' strategic partnership. Bahrain hosts the U.S. Navy's Fifth Fleet.

Al-Singace was sentenced to life in prison four years ago after being charged as a coup plotter.