HAVANA (AP) -- Communist leaders called Tuesday for the revolutionary ideals of leader Fidel Castro to live on as they marked the 50th anniversary of a failed attempt to assassinate dictator Fulgencio Batista.

"This revolution will continue for all time," parliament speaker Ricardo Alarcon told hundreds of students and top government leaders, including acting president Raul Castro, who watched the event from a front row seat but did not address the crowd.

Alarcon praised the courage of Jose Antonio Echeverria, the University Student Federation president who was killed by police after the attack a half-century ago, and said that Cubans like him would ensure the socialist revolution would endure.

The 80-year-old Castro announced on July 31 he had undergone intestinal surgery and was temporarily ceding power to his brother Raul, the defense minister.

Echeverria was 19 on March 13, 1957, when he led a group of college students in the attack. A three-story, black-and-white photo of a beaming and pudgy Echeverria smiled down on those assembled.

The students seized the local Radio Reloj station and announced Batista's death, unaware that he had survived. Echeverria was shot and killed by police minutes later.