The UN voiced its alarm on Friday about the detention of Nabeel Rajab, the director of the Bahrain Center for Human Rights (BCHR), on Wednesday for tweeting a message that allegedly offended the country’s Interior Ministry, press tv reported.
"We urge Bahraini authorities to immediately release Nabeel Rajab and all other individuals detained for peaceful exercise of their rights," said Rupert Colville, the spokesman for the UN Office of the High Commissioner for Human Rights (OHCHR), at a press conference in the Swiss city of Geneva.
Colville also said the detention of Rajab sends a "chilling message" to others in Persian Gulf Arab states, inferring that they could also face reprisals if they speak out.
"Human rights defenders in Bahrain must be able to carry out their work without fear of reprisals," he added.
Meanwhile, the New York based HRW called for Rajab to be released, saying that Bahrain wishes to "silence its critics" with such actions.
Nabeel was under the regime’s custody in Jaw prison in Eastern Bahrain from July 9, 2012 until May this year.
Earlier in September, the European Parliament held a meeting with a delegation from the BCHR headed by Rajab.
Since mid-February 2011, thousands of pro-democracy protesters have held numerous demonstrations in the streets of Bahrain, calling for the Al Khalifa royal family to relinquish power.
On March 14, 2011, troops from Saudi Arabia and the United Arab Emirates invaded the country to assist the Bahraini government in its crackdown on peaceful protesters.
According to local sources, scores of people have been killed.