The government in Bahrain announced this week that it revoked the citizenship of 31 people considered a threat to national security.
Joe Stork, deputy director of Middle East affairs for the rights group, said there's no justification for equating political dissent with national security.
"Bahraini authorities have been increasingly targeting opposition activists and this decision takes it to a new level," he said in a statement from Beirut.
At least one of the people stripped of their citizenship belonged to the opposition al-Wefaq party, which the government blamed for some of the unrest in the country. Taimoor Karimi, a lawyer included in the list, told the rights group he wasn't aware he was targeted until he heard of it in the media.
Bahrain was criticized recently for issuing a ban on public demonstrations until security was restored in the country. Two foreign nationals were injured in a series of bombings in Manama this week. The official Bahrain News Agency reports that a civilian vehicle was damaged by a bomb Thursday in the capital city.
More than 40 people were killed during anti-government clashes last year. The government said it was committed to reforms outlined by an independent commission that examined last year's unrest.