An international human rights group on Friday criticized the president of Venezuela's parliament for questioning the legitimacy of activists who last week had testified before the United Nations Human Rights Council in Switzerland.

Among those who spoke to the Geneva-based body was Lilian Tintori, the wife of jailed opposition leader Leopoldo López, who insisted that the "75 political prisoners in Venezuela have to be set free immediately," according to El Nuevo Herald.

But Diosdado Cabello, the National Assembly leader who is widely considered the second most powerful man in embattled President Nicolás Maduro's administration, accused Tintori and others of "conspiracy" and "attacks" against their country, the independent International Service for Human Rights (ISHR) said in a statement.

Speaking on his nationally broadcast television show, Cabello also "stigmatized" Feliciano Reyna, a respected Venezuelan AIDS activist, by revealing his recent migratory record and charging that he owned a business worth $1 million in Panama, the organization detailed.

Ben Leather, a spokesman for ISHR, called the socialist leader's accusations "dangerous and irresponsible."

"These honorable, dedicated and highly respected human rights defenders have only one interest, namely respect for human rights in Venezuela," Leather said. "They have come to Geneva to provide first-hand information to the U.N. Human Rights Committee about the human rights situation in Venezuela and to discuss how the Venezuelan authorities might better guarantee the rights of their people," he added.

In a press conference held on Monday in Caracas, Reyna, for his part, further upped the ante by saying that Cabello was lying about him and his fellow human rights advocates, El Universal noted. The suggestion that he owned a foreign enterprise, for example, was completely false, Reyna said.

In a joint statement with the Rev. Raúl Herrera, constitutional attorney Carlos Ayala Corao and activist Deborah Van Berkel, he called on Cabello to cease his attacks.

"A number of organizations, including those defending human rights, repudiate the way in which the Venezuelan authorities have systematically ignored U.N. bodies' repeated requests to guarantee the security and integrity of those defending human rights, as well as the failure to comply with orders issued by the Inter-American Commission on Human Rights," the group wrote.