(CNN) -- The king of Bahrain has decreed that the country's state of emergency will end June 1, state media reported Sunday.

Massive anti-government protests prompted King Hamad al-Khalifa's March 15 declaration of a three-month state of emergency in Bahrain, a strategically important kingdom and U.S. ally.

Witnesses reported violent crackdowns on protesters after the state of emergency was imposed.

Meanwhile, a trial has started for 21 suspects accused of fostering the unrest, the official Bahrain News Agency reported Sunday. A hard-line Shiite opposition group and a leading human rights activist were among those on trial.

The suspects face accusations of "terrorist attempts to topple the regime forcibly in collaboration with a terrorist organization working for a foreign country," the government-run news agency said.

Human rights groups said forces have raided hospitals, targeting doctors and patients, during the state of emergency.

More than 40 doctors and nurses faced prosecution last week on charges that included having supported "the saboteurs and the calls to bring down the political regime," the news agency said.

Government officials in Bahrain denied targeting hospitals.

The protests started in February, when young members of the country's Shiite Muslim majority staged protests to complain about discrimination, unemployment and corruption -- issues they say the country's Sunni rulers have done little to address.

Bahrain's ruling Khalifa family is Sunni Muslim, but about two-thirds of the country's people are Shiite.

Hard-line protesters have called for the abolition of the country's royal family altogether.

Bahrain is home to the headquarters of the U.S. Navy's Fifth Fleet, the naval arm of American power in the region.

In a speech last month, the country's crown prince defended the government's actions.

"We were immensely concerned that some of our youth were pushed towards a destructive path and that the nation was drawn along with them," Prince Salman bin Hamad al-Khalifasaid, according to an official transcript.

"We took necessary action to preserve lives and the livelihood and interests of all the people, based on our commitment to Islamic and Arab values," he said.

CNN's Jennifer Fenton contributed to this report.