“I am deeply concerned that opposition leaders Leopoldo Lopez and Antonio Ledezma have again been taken into custody by Venezuelan authorities after their house arrest was revoked,” said UN High Commissioner for Human Rights Zeid Ra'ad Al Hussein in a statement issued by his Office (OHCHR).

He urged the Government to immediately release all those being held for exercising their rights to freedom of peaceful assembly, association and expression, noting that the UN Working Group on Arbitrary Detention considers the detention of both Lopez and Ledezma to be arbitrary.

President Maduro has declared victory in Sunday's elections for the new body, which could replace the current National Assembly.

Zeid also expressed his regret that at least 10 people reportedly died over the weekend amid demonstrations over Sunday's polls, calling for a prompt, effective and independent probe into these deaths.

He urged the authorities “not to make an already extremely volatile situation even worse” through the use of excessive force, including through violent house raids that have occurred in various parts of the country.

“I appeal to all parties to refrain from the use of violence,” he said.