CARACAS, Venezuela, Nov. 1 (UPI) -- Venezuelan President Nicolas Maduro's regime on Monday released five politicians the opposition considers were political prisoners a day after Vatican-mediated negotiations began.
The opposition representatives released were Carlos Melo, Andres Moreno, Marco Trejo, Andres Leon and Angel Coromoto Rodriguez. The men were held on charges ranging from carrying an explosive device and undermining the morale of the armed forces -- charges they denied.
Maduro and Democratic Unity Roundtable, or MUD, opposition leaders met on Sunday in Caracas for crisis-related talks mediated by the Vatican.
MUD leader Jesus "Chuo" Torrealba on Monday called for the release of political prisoners -- warning that the negotiations would end if the demand was not met.
"We believe that without concrete gestures, without the release of political prisoners in the coming days, this dialogue process can not continue. Our proposal is to require early release of political prisoners in the coming hours, days," Torrealba said.
President Barack Obama sent Under Secretary of State for Political Affairs Thomas A. Shannon, Jr. to Caracas on Monday to aid in mediation efforts. He is scheduled to stay until Wednesday.
"Ambassador Shannon will meet with senior government officials, members of the political opposition, and representatives of civil society," the U.S. Department of State said in a statement. "His visit will underscore our support for the ongoing dialogue process, and our interest in the well-being of the Venezuelan people."
Venezuela is undergoing a political and economic crisis which the opposition and Maduro's regime accuse each other of worsening. The opposition's attempts to hold a recall referendum to oust Maduro from the presidency were postponed by the country's National Electoral Council in October.