Updated

HAVANA -- Raul Castro's daughter and an anti-government blogger are mixing it up in Cuban cyberspace.

Mariela Castro opened a Twitter account and sent her first tweets Tuesday about her work as head of Cuba's National Sex Education Center. She's an advocate of gay rights.

Dissident blogger Yoani Sanchez fired the first Twitter salvos, welcoming her to the social network and asking when Cubans "will be able to come out of other closets."

Castro shot back that Sanchez ought to study up, saying Sanchez's version of tolerance reinforces "the old mechanisms of power." She later grumbled about tweets from unspecified "despicable parasites."

Cuba has a small but growing Twitter community despite the second-worst Internet connectivity in the world.