Washington (CNN) U.S. and Cuban officials began a historic round of talks on Wednesday to bridge a 50-year rift in diplomatic relations, but just a day later, the Cuban delegation slammed the United States on its human rights track record.

Cuban diplomats announced in a statement Thursday that in discussions with American officials they expressed their "serious concerns" over human rights in the United States, citing everything from detentions at Guantanamo Bay, to "police abuse" in Ferguson and New York to racial and gender inequalities.

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The sniping comes just before Roberta Jacobson, the head of the U.S. delegation, was set to meet Friday morning with the "Ladies in White," the wives and other female relatives of Cuban political prisoners, and other dissident groups.

Cuban officials also suggested "building up on the positive experience achieved in Cuba with regard to the enjoyment of human rights" and pointed to Cuba's efforts to improve human rights in the world.

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