GWEN IFILL: Now: Cuba releases political prisoners, and Fidel Castro reappears.
Margaret Warner has that story.
MARGARET WARNER: Flanked by their families, seven former Cuban political prisoners arrived in Madrid today as free men. Smiling and flashing victory signs, the dissidents are the first of 52 such prisoners that Cuba has promised to free. It will be the biggest such release in a dozen years.
JULIO CESAR GALVEZ RODRIGUEZ, released Cuban prisoner (through translator): We are the first of a group of prisoners of conscience who have just landed on Spanish soil, after more than seven years being unfairly jailed and in captivity.
MARGARET WARNER: The package was brokered in talks earlier this month among the Cuban government, the Catholic Church, and Spain's foreign minister.
RICARDO GONZALEZ ALFONSO, released Cuban prisoner (through translator): Change is inevitable. In my reply to you, I don't want to end it without thanking the Spanish government for its role in this dialogue.
MARGARET WARNER: Estimates of how many political prisoners remain there vary widely, but the Cuban Commission on Human Rights in Havana says there are 160, the fewest in half-a-century.
The releases have created the biggest international splash of Raul Castro's four-year presidency. He took over when his brother Fidel relinquished the post following intestinal surgery.
But, last night, Fidel Castro reemerged, with his first televised remarks in three years. He was interviewed on state-controlled Cuban television. In 75 minutes, the 83-year-old revolutionary never mentioned the prisoner release or any other domestic Cuban issue. Instead, he warned that the U.S. was increasing the danger of nuclear war with Iran.
FIDEL CASTRO, former Cuban president (through translator): The U.S. will encounter a terrible resistance that will spread the conflicts and cannot end up any other way than nuclear.
MARGARET WARNER: And he blamed the March sinking of a South Korean naval ship on the United States, not North Korea.
FIDEL CASTRO (through translator): What is going to be hard, it will take a lot of work for them to admit, the U.S., is that they were the ones that sank it.
MARGARET WARNER: Some Cubans said they were heartened to see their former leader last night.
MIGDALIA QUEIPO TORRES, Cuba (through translator): I think his health is very important for our country. I am very grateful to all the doctors. A thousand hugs and kisses for him now that he has come on the television again.
MARGARET WARNER: It's his second appearance in less than a week. Days ago, a pro-government blog posted photos of him visiting a Havana think tank.
In Washington today, State Department spokesman P.J. Crowley called for all Cuban political prisoners to be freed, but added:
P.J. CROWLEY, U.S. assistant secretary of state for public affairs: This is a positive development that we hope will represent a step towards increased respect for human rights and fundamental freedoms in Cuba.
MARGARET WARNER: The prisoner releases and Fidel Castro's public reemergence come as the U.S. is reevaluating its trade and travel embargo against the Caribbean nation.
Last year, President Obama ended restrictions on Cuban-Americans visiting relatives. And, last month, a House committee approved a bill to end the travel ban for all Americans and ease trade restrictions on U.S. exports to Cuba.