Vietnam jailed a prominent blogger for 15 months on Wednesday on a charge of anti-state activity, the second such sentencing in a fortnight, prompting rights groups to condemn the alleged muzzling of dissent in the communist country. Pham Viet Dao, 61, a Communist Party member and a former official at the Ministry of Culture, was charged with "abusing democratic freedoms to infringe on the interests of the State" after a half-day trial in Hanoi. In addition to his own blogs, Dao's popular site included links to dozens of other commentaries critical of Vietnam's politics and society. The court ruled that the posts "defamed the party and state... blackening the honour and prestige of the (communist) party leader and the prime minister," presiding judge Ngo Tu Hoc said. "His online distortion and defaming of party and state leaders caused confusion over the party leadership and undermined people's trust in the party," Hoc added. Dao, who appeared calm in court, apologised for "having posted some incorrect information," but added that he did not think his posts had "badly influenced society." The Paris-based International Federation for Human Rights (FIDH) condemned the sentence and called for the release of an estimated 200 political prisoners. "Vietnam continues to behave as an authoritarian government that perceives every freedom, including freedom of opinion and expression, as a threat to its rule,? said FIDH President Karim Lahidji. "Vietnam must end the harassment, arrest, and imprisonment of dissidents." International rights groups said lawyers, bloggers and activists in the country are regularly subject to arbitrary arrest and detention. Two weeks ago, popular blogger and journalist Truong Duy Nhat was jailed for two years for the same charge, which prompted the US to say it was "deeply concerned" by the sentence and similar criticism from france. According to Reporters Without Borders, Vietnam was second only to China in the number of bloggers it detained, with at least 34 currently behind bars. Communist Vietnam bans private media, with all its newspapers and television channels state-run. However, many citizens now prefer to access news through blogs and social media.