Bahrain has blocked three websites it said were implicated in fuelling sectarian strife, said the official state news agency of the Gulf kingdom, which has a majority Shiite population and is ruled by Sunni Muslims.
The move comes after Prime Minister Sheikh Khalifa bin Salman al-Khalifa set up a committee this week to monitor sectarianism and comments disparaging the royal family in the media, religious sermons or on the Internet.
"The Ministry of Information has issued a decision to shut down three Internet sites found implicated in stoking sectarian strife in Bahrain, which is in breach of the press and publication law," the Bahrain News Agency report said.
A local newspaper said the blocked sites included one close to the main Shiite opposition group, al-Wefaq. The websites were accessible for web surfers outside Bahrain on Tuesday.
"We are with the idea of fighting sectarianism and support national unity, but we are worried the committee will stop any opposition views," Wefaq spokesman Faheem Abdulla told Reuters.
"We are calling for clear definitions of sectarianism ... if there is balanced opposition, it should not be blocked, whether Sunni or Shiite," he said.
Last week, thousands of Shiites protested in Bahrain against a Sunni politician's comments they said insulted a Shiite cleric revered in the U.S.-allied island of about 1.05 million people.
Shiites have long complained of alleged discrimination in jobs and services, a charge the government denies.
In 2006, Bahrain appointed a Shiite as a deputy prime minister for the first time since its independence in 1971.
The country, home to the U.S. Fifth Fleet, witnessed anti-government riots and protests in the early 1990s which the authorities said were led by Shiite opposition groups.