Bahrain has forbidden Sheikh Kamel al-Hashemi, Adel al-Hamad and Mohammed al-Mansi to preach in and around the capital Manama.

Bahrain has banned three Muslim clerics from preaching in mosques, accusing them of violating the “ethics and principles of religious discourse”, in what opposition activists said was part of a crackdown on dissent.

State news agency BNA said the Ministry of Justice and Islamic Affairs and Interior Ministry of the Sunni Muslim-ruled kingdom had forbidden Sheikh Kamel al-Hashemi, Adel al-Hamad and Mohammed al-Mansi to preach in and around the capital Manama.

It said the three had ignored warning from authorities to stick to rules set for preachers. Bahrainis said at least two of them were Shi’ites. Majority Shi’ites led mass protests in the island state in 2011.

“Instead, they maintained their approach of violating the ethics and regulations of the religious discourse, using the same tone, method and language that does not befit the sanctity of the pulpit, thus prompting intervention to stop this violation,” BNA quoted the ministry as saying, without giving details.

The main opposition Al-Wefaq group, in a statement posted on its website on Friday, condemned the decision.

“The regime is practising the ugliest form of restriction … on freedom of speech and … freedom of thought and belief,” it said.

It said such measures were “part of a systematic approach to avoid giving the Bahraini people their political rights to build a democratic system based on justice and equality”.

The opposition says the government has stepped up a crackdown on opponents ahead of elections expected later this year, which it has threatened to boycott unless the government gives assurances that any vote reflects the will of the people.

Last month, the Ministry of Justice and Islamic Affairs petitioned courts to temporarily suspend the activities of three opposition groups for violating Bahraini laws or their own internal regulations.

In January, a court ordered the dissolution of the Islamic Scholars’ Council, an association of senior Shi’ite Muslim clerics, declaring it illegal, saying it was not an officially registered body.

Many Shi’ites complain of political and economic discrimination, a charge the authorities deny.

Bahrain, a key Western ally and home to the U.S. Fifth Fleet, blames Shi’ite Iran for unrest and says it has made many reforms since 2011.

Last month, Bahrain ordered U.S. Assistant Secretary of State for Democracy, Human Rights and Labor Tom Malinowski to leave the country after he met leaders of Al-Wefaq.

Earlier this month, Bahraini authorities charged Al-Wefaq leader Sheikh Ali Salman and his political assistant, Khalil al-Marzouq, with holding an illegal meeting with a U.S. diplomat.