HAVANA (AP) ― Amnesty International said Monday that three Cubans held without charge for 52 days following their arrest at a protest were released last week, hours after the human rights group named them as prisoners of conscience.

The release of the three also came a day after a hunger-striking dissident died, prompting condemnation from island dissidents, rights watchers, the United States and other nations. Amnesty had planned to designate Wilman Villar, 31, a prisoner of conscience but he died in custody before it could.

Ivonne Malleza Galano, Ignacio Martinez Montejo and Isabel Haydee Alvarez were set free Jan. 20 but threatened with “harsh sentences” if they do not stop their anti-government actions, the human rights monitor said in a statement Monday.

It said all three were detained at a Nov. 30 protest in Havana at which Malleza and Martinez held a banner that read “Stop hunger, misery and poverty in Cuba.” Alvarez was arrested for objecting when security forces took the other two into custody.

“Amnesty International had adopted them as prisoners of conscience, as they were detained solely for exercising their right to freedom of expression and freedom of assembly, and had called for their immediate and unconditional release,” the statement said.

Cuba considers dissident activity to be counterrevolutionary, and the dissidents to be mercenaries out to bring down the communist-run government. It denies holding any political prisoners in its lockups.

Amnesty, which has strict criteria for who constitutes a “prisoner of conscience” including a history of nonviolence, had not recognized any Cuban inmates as such since the previous spring, when the last of 75 dissidents jailed since a 2003 crackdown were freed.

Villar was arrested in November in the eastern city of Santiago following an anti-government protest.

The Cuban government denied that he had been on hunger strike or was even truly a dissident. It described him as a “common criminal” sent to prison for domestic violence, said he received all the medical attention he needed and alleged that his case was being manipulated for political ends.