Reuters: Bahrain hit back at U.S. expressions of concern over the Gulf Arab kingdom's treatment of opposition figures on Wednesday, saying all its actions followed due legal process.

The State Department on Tuesday said the arrest of Ibrahim Sharif, prosecution of Majeed Milad and reports that a case against Ali Salman, head of Bahrain's main opposition group, had been reopened, "raise serious concerns about restrictions on freedom of expression".

In response, Bahrain's Foreign Ministry said in a statement the individuals were detained on the basis of criminal acts not political expression. "The government of Bahrain will not tolerate incitement to violence, and it is the government's duty to protect citizens, residents and visitors alike," it said.

Bahrain, which hosts the U.S. Fifth Fleet, has experienced sporadic unrest since 2011 when its security forces ended mass protests calling for democracy in the country, which has a Shi'ite Muslim majority but a Sunni ruling family.

The opposition says the government, backed by its Sunni ally Saudi Arabia, is attempting to stifle free speech by detaining, prosecuting and jailing peaceful political dissidents.

The government has accused the opposition of stirring up violent protests and of links to Shi'ite Iran, which both it and Tehran deny.

The official BNA news agency said on Monday Rajab had been freed from a six-month jail term imposed in May for insulting the authorities. It cited health reasons for the release.

Last year Bahrain denied entry to a U.S. congressman seeking to meet opposition figures, and expelled U.S. Assistant Secretary of State for Democracy, Human Rights and Labor Tom Malinowski for meeting Ali Salman.

Bahrain's King Hamad did not attend a summit between U.S. President Barack Obamaand Gulf Arab leaders at Camp David in May, choosing instead to send his crown prince while himself attending a horse show with Britain's Queen Elizabeth.