Hamell Santiago Maz Hernández, a Cuban dissident awaiting trial in the nation’s most notorious maximum security prison on a charge of “disrespect” for the Revolution, died in mysterious circumstances in late February. Now, fellow dissidents at the prison fear eating government-issued food, worried that the government poisoned their colleague.

Maz Hernández, a member of the Patriotic Union of Cuba (UNPACU), died on February 24 while awaiting a trial on the charge of desacato, a vague crime that roughly translates to “disrespect” and which police often use against anti-communist dissidents. Maz Hernández spent eight months in Combinado del Este, a maximum security prison, without access to the outside world.

According to the official UNPACU statement on his death, Maz Hernández was 45 years old. State officials told his wife that he died of cardiac arrest.

“This is the version of the jailers,” the UNPACU statement reads. “The Patriotic Union of Cuba will continue to seek, with as many close sources as we can find, the true causes that ended this peaceful dissident’s life.”

Maz Hernández had previously conducted a 30-day hunger strike against his arrest, arguing that he had not acted in any way to merit his arrest on “disrespect” charges. José Daniel Ferrer, the head of UNPACU, posted a final photo of Maz Hernández on Twitter, sending a message to American President Donald Trump reading, “others can die if we do not condemn this tyranny.”

President Trump has repeatedly condemned the Cuban Communist dictatorship and criticized his predecessor, Barack Obama, for negotiating with the regime of dictator Raúl Castro.

Following Mas Hernández’s death, other UNPACU members who remain behind bars have begun to reject prison food, according to a report from the Miami-based Martí Noticias. At least five other UNPACU members – Ismael Boris Reñi, Alberto Valle, Yosvani Sánchez Valenciano, Ihosvani Martínez Lemus, and Alexander Alain Rodríguez – have declared themselves on hunger strike because they “fear being poisoned,” according to UNPACU organizer Zaqueo Báez.

“We are worried because the prison’s hygienic conditions get worse day by day, the prisoners are exposed to diseases through water and food,” he added. “Once they begin a hunger strike, they are isolated and the family loses all contact with them.”

Báez himself has repeatedly been arrested for anti-communist activity, once making international headlines for his arrest in front of Pope Francis. Báez had spoken the word “freedom” too close to the Pope’s vehicle, earning him a “disrespect” charge. Pope Francis later denied any knowledge of the incident.

Combinado del Este is a preferred maximum security prison for Cuban dissidents. Among those that have spent time in the prison is Danilo Maldonado Machado, a graffiti artist known as “El Sexto.” Police transferred him to Combinado del Este in December, following a month in detention for having publicly celebrated the death of Fidel Castro. Following his release, Maldonado accused police of repeatedly beating and torturing him, threatening him with execution. He was never charged with any crime, and the government released him without warning.

The Cuban Commission for Human Rights and National Reconciliation (CCDHRN), an NGO dedicated to tracking the arrest and abuse of dissidents on the island, issued a statement condemning Maz Hernández’s death and warning that violence against dissidents has increased since President Obama’s “normalization” process with the Castro regime began in 2014. “Thousands of Cubans have died under government custody and all moral and legal responsibility falls on the government,” the organization declared.

Maz Hernández joins some Cuban dissidents who have died in mysterious circumstances, from the founder of the Ladies in White, Laura Pollán, to the Christian Liberation Movement leader Oswaldo Payá. While the government has not hesitated to allow dissidents to die – and potentially involve itself in those deaths – when the international community has not protested, incidents exist in which the Communist Party has intervened to prevent the death of a dissident. Most recently, the Cuban government forced dissident Vladimir Morera Bacallao to eat after over 80 days on a hunger strike. His family claims Morera was drugged and deceived into eating against his will, a UN-designated violation of human rights.