Turk arrived in Venezuela on Thursday and met with President Nicolas Maduro on Friday, in addition to Vice President Delcy Rodriguez, senior government officials, opposition figures and victims of human rights violations.

"In my meetings with the president and ministers, I called for all people who have been arbitrarily detained to be released," Turk said on Saturday in a statement.

Turk extended his call to governments around the world to release, pardon or grant amnesty to "all those arbitrarily detained for exercising their fundamental human rights."

During his trip, Turk said he met with people who were arbitrarily detained and tortured.

In September, a U.N. independent international fact-finding mission on Venezuela said state security agencies have for years used sexual- and gender-based violence to torture and humiliate detainees.

"I was given commitments that torture complaints would be addressed decisively, fully investigated and those responsible brought to justice," Turk said.

The High Commissioner's visit comes after Venezuela's National Assembly on Tuesday passed the first of two readings of a bill to regulate non-governmental organizations (NGOs), which has sparked criticism from advocacy groups.

On the subject, Turk said he reiterated to authorities the importance of guaranteeing civic space.

The most recent Venezuela report by a U.N. High Commissioner for Human Rights, made last June, said Venezuela had taken some steps to strengthen the rule of law, but that there were still concerns about the lack of independence of the judicial system.