The International Press Institute (IPI) today reiterated its demand that Cuban authorities immediately release the independent journalist Calixto Martínez Arias, who was imprisoned last September for allegedly insulting former president Fidel Castro and his brother, current president Raúl Castro, under the country’s criminal-defamation laws.

Last week, Martínez ended his second hunger strike in less than four months in protest of conditions at Cuba’s Combinado del Este prison after authorities apparently promised to release him. This promise has not yet been fulfilled, according to Roberto Guerra, director of the independent news agency Hablemos Press, where Martínez worked as a correspondent.

“Calixto remains in Combinado del Este and I am not sure that they are going to free him,” Guerra told IPI. “I will believe it [the promise of his release] when I see him in our house.”

Authorities have accused Martínez of desacato under Article 144 of the Cuban Criminal Code, which punishes insulting or offensive speech toward public officials with up to three years in prison. However, the Cuban government has given no official explanation for the accusations against Martínez, nor have any charges been filed in court.

“This case is clear example of how criminal defamation and insult laws can be abused by governments to shut down independent voices and should be repealed,” IPI Executive Director Alison Bethel McKenzie said today. “Calixto Martínez should be released from prison immediately and unconditionally.”

Guerra said last week that Martínez had lost two teeth and had lesions on his lips and tongue. In January, Amnesty International (AI) named Martínez a “prisoner of conscience.” Amnesty reported that Martínez was being held around-the-clock in an isolation cell without light, hygienic facilities, or bed sheets.

Martínez was detained on Sept. 16, 2012 near Havana’s José Martí International Airport, where he was apparently investigating the arrival of medical supplies in connection with an outbreak of cholera and dengue fever on the island.

Martinez had previously written a series of articles on the outbreak, which the Cuban government has been accused of playing down. In one article, published Sept. 14, 2012, Martínez reported on a series of deaths in the city of Camagüey, in central Cuba, believed to be caused by dengue fever. He accused authorities of maintaining “airtight control” over medical stations so as to “impede information about the exact number of the dead” from the disease.

The supposed “promise” to release Martínez comes as IPI prepares to travel to the Caribbean for a second time as part of its campaign to repeal criminal defamation laws across the region. IPI has long warned that such laws risked being misused by governments intolerant of criticism or investigative journalism.

Bethel McKenzie added: “Criminal defamation laws, including desacato laws, are being actively used in the Caribbean to punish journalists for doing their job. All who value freedom of expression in the Caribbean should be deeply concerned about the existence of such laws, and should join us in lobbying governments for their removal from criminal statutes.”

According to IPI research, six Caribbean countries – Antigua and Barbuda, Cuba, the Dominican Republic, Grenada, Haiti, and Suriname – have used such laws to prosecute journalists in the lat 15 years. Two journalists were sentenced to prison for libel in the Dominican Republic last year, though both convictions were overturned on appeal, following protests by IPI.

However, all 16 independent states in the Caribbean retain some form of criminal defamation law. Since the beginning of IPI’s campaign, Grenada has abolished the offence of criminal libel and the Dominican Republic has eliminated prison sentences for defamation from its draft penal code. A bill that would abolish criminal libel in Jamaica was tabled before parliament at the end of March.