He is facing multi-million-dollar corruption charges relating to a previous term as governor of Zulia state.

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At the time he was the governor of Zulia, Venezuela's richest and most populous state.

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Mr Arias may find it hard to increase his own support, especially outside Zulia.

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Sabino Romero was reportedly stopped by two masked men on the El Tukuko motorway in the western state of Zulia.

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