On Monday, the Cuban government published 21 photographs of Fidel Castro in an apparent effort to quell rumors about the health of the 88-year-old revolutionary leader.

CNN reported the pictures, released late Monday in the online version of Cuba's state-run newspaper Granma, show Castro and his wife, Dalia Soto del Valle, with Randy Perdomo Garcia, the leader of the student association of the University of Havana. The men are seated, looking at a newspaper and watching TV.

Concerns multiplied when the leader of the 1953-1959 Cuban Revolution limited his comments on the planned restoration of diplomatic relations between his country and the United States to a letter published in Granma. In the missive, Castro endorsed the steps taken by his brother and successor, Raul, though he said he "did not trust" Washington.

Granma said the meeting between Castro and the student leader came four days before his comments on the U.S.-Cuba thaw, Agence France-Presse detailed. Perdomo said he and the former president discussed other writings, astronomy and the importance of science in human advancement.

The meeting and photographs were not the first attempt by Cuban state media to underline that Castro remains fit and lucid. Last week, Castro received Brazilian theologian Frei Betto, an advocate of liberation theology, which emphasizes the Catholic Church's responsibility to help the poor.

Although Betto insisted that "the commander is in good health and in good spirits," no photos of their encounter were published. The theologian said Castro took notes on their discussions.

In mid-January, the Communist leader also sent a letter to soccer star Diego Maradona, a friend of his.

Castro has not been seen in public since Jan. 8, 2014, when he attended an art gallery opening near his home. No pictures of him have been published since August, and "rumors of his demise" have been frequent since he stepped down from Cuba's presidency according to Agence France-Presse.

Castro survived "scores of CIA assassination attempts" and a failed U.S. invasion of Cuba, according to CNN. After he and a band of guerrillas overthrew dictator Fulgencio Batista's government in 1959, he served as the island nation's head of state until 2006; his resignation was linked to an intestinal ailment.