Bernie Sanders was asked about backlash he received praising Fidel Castro's literacy program in Cuba while also denouncing the authoritarian leader.

WASHINGTON — Democratic front-runner Bernie Sanders came under fire Monday from Florida Democrats and his 2020 rivals over comments he made partially defending Fidel Castro.

His views were examined in a "60 Minutes" piece regarding some of his past comments on authoritarian regimes. Sanders argues, like some of his Democratic rivals in the race for president, that the very rich should pay higher taxes. Sanders says he has been preaching the same populist and progressive message for decades now, as 60 Minutes points out.

During the interview, Anderson Cooper asked Sanders about his comments made in the 1980s regarding Fidel Castro's Cuba. Sanders explained back then why he felt the Cuban people didn't rise up against Castro and help the U.S. overthrow the regime. "He educated their kids, gave them health care, totally transformed the society," Sanders said.

On "60 Minutes," Sanders responded to his past comments telling Cooper, "We're very opposed to the authoritarian nature of Cuba but you know, it's unfair to simply say everything is bad. You know? When Fidel Castro came into office, you know what he did? He had a massive literacy program. Is that a bad thing? Even though Fidel Castro did it?" Sanders said.

When Cooper pressed Sanders regarding dissidents that have been imprisoned in Cuba, Sanders said he's against it.

"We condemn that. Unlike Donald Trump, let's be clear, you want to-- I do not think that Kim Jong Un is a good friend. I don't trade love letters with a murdering dictator. Vladimir Putin, not a great friend of mine," Sanders stated.

Sanders is a self-described democratic socialist, and he scored a commanding win in the Nevada caucuses, which has given him two consecutive victories after a tie for first in Iowa.

His "60 Minutes" comments were criticized by at least two of his campaign rivals.

“Fidel Castro left a dark legacy of forced labor camps, religious repression, widespread poverty, firing squads, and the murder of thousands of his own people,” tweeted former New York City Mayor Mike Bloomberg. “But sure, Bernie, let’s talk about his literacy program.”

"After four years of looking on in horror as Trump cozied up to dictators, we need a president who will be extremely clear in standing against regimes that violate human rights abroad," tweeted former South Bend Mayor Pete Buttigieg. "We can't risk nominating someone who doesn't recognize this."

The president of the Democratic Hispanic Caucus in Broward County, Lourdes Diaz, told the New York Times they were "totally disgusted and insulted."

Republican Senator Marco Rubio wrote on Twitter, "ultimately Marxism fails to deliver “security” & you don’t have the freedom to do anything about it."

Sanders was asked again about the comments Monday at a CNN Town Hall after his "60 Minutes" interview drew backlash from some Democrats.

"When Fidel Castro first came to power ... you know what he did? He initiated a major literacy program. There was a lot of folks in Cuba at that point who were illiterate," Sanders said. "And they helped people learn to read and write. You know what? I think teaching people to read and write is a good thing."

Sanders then went on to list several countries under authoritarian rule, including Cuba, that he says he has criticized. He also mentioned China on that list, but said China has taken more people out of extreme poverty than any country in history.

Sanders also said the Democrats criticizing him for his comments are supporting other candidates.

As 60 Minutes reported, Sanders was recently told by U.S. intelligence that Vladimir Putin and his government has tried to help out the Sanders campaign. Lawmakers were also reportedly briefed last week that Moscow is working to try and help re-elect President Trump.

Sanders said, "As president of the United States, Mr. Putin, you will not interfere in our elections.''

Sensing the prospect of a knock-out punch in South Carolina this weekend, Sanders is ramping up his outreach in the state where Joe Biden has long been the heavy favorite.