Al-Wefaq supporters hold portraits of leader Sheikh Ali Salman on May 29, in protest against his arrest.
Abu Dhabi CNN  — 

A Bahrain court has suspended the main Shiite opposition party and frozen its assets – a move that threatens to bring unrest to the tiny island kingdom five years after it was shaken by huge Arab Spring protests.

The Ministry of Justice accused the group, known as al-Wefaq, of working “to create a new generation that carries a spirit of hatred,” promoting sectarian tension and securing “legal cover for acts associated with extremism and terrorism,” the official Bahrain News Agency (BNA) reported.

The decision to suspend al-Wefaq came a day after prominent rights activist Nabeel Rajab was detained after a dawn raid on his home.

Rajab, who previously spent two years in prison on charges relating to pro-reform protests, is accused of “spreading false news and rumors … in a bid to discredit Bahrain,” BNA reported.

Last month an appeals court sentenced al-Wefaq’s Secretary General Ali Salman to nine years in prison – doubling his initial sentence – on charges including “promoting forceful change of the political regime,” inciting disobedience and inciting sectarian hatred.

U.S. State Department spokesman John Kirby said Wednesday that Washington was “deeply troubled” by the news of al-Wefaq’s closure and “urged Bahraini officials to reconsider this decision.”

Human Rights Watch condemned the move on Thursday, saying authorities did not have evidence to support their allegations.

“Nobody should be under any illusion as to what Bahrain’s rulers are up to – nothing less than squeezing the life out of its peaceful opposition movement,” said Joe Stork, the deputy Middle East director at Human Rights Watch. “Bahrain’s once vibrant activist community is in danger of being wiped out and Bahrain’s friends in the UK government are failing to speak out against this dangerous and totally unjustified action.”

‘Critical security partner’

The tiny Gulf nation is a close U.S. military ally and host to the U.S. Navy’s Fifth Fleet. During a visit in April, Secretary of State John Kerry described the kingdom as a “critical security partner” in the region.

Bahrain, a majority Shiite country ruled by a Sunni minority, has made headlines over the last five years after pro-reform protests sparked a government crackdown.

Journalists freed amid opposition protests

In 2011, at the height of the Arab Spring, Bahraini citizens demanded democratic reforms and other changes in the way the country was run.

The kingdom continues to witness sporadic clashes between protesters and security forces, mainly in Shiite majority neighborhoods outside the capital, Manama.