Hernan Dario Velasquez was a negotiator in 2016 peace agreement, but announced three years later he had rearmed.
The observers reported polls saw better conditions than previous years, but raised concerns over some practices.
Head of EU observer mission says while ‘better conditions’ marked weekend vote, some problems persisted.
About 42 percent of eligible voters cast ballots in Sunday’s vote, which saw Venezuelan opposition suffer heavy defeat.
The elections are the first in 15 years to include international observers.
Nicolas Maduro’s allies win 20 of 23 governor posts in polls that saw the participation of opposition after four years.
The polls mark the first time in four years that the main opposition parties will participate in an election.
Opposition will contest elections on Sunday, to be monitored by the EU observers, for the first time in four years.
Saab is accused of paying bribes to siphon $350m from state contracts to build housing for Venezuela’s government.
The so-called ‘Citgo 6’ have been held since 2017, with the US accusing Caracas of using the group as a bargaining chip.
President Nicolas Maduro says Venezuelan government respects ICC decision to open probe, but ‘we do not share it’.
Judge keeps in place one charge of conspiracy to commit money laundering, which carries maximum 20-year prison sentence.
‘For us the return to classes is important, but we have doubts,’ said an official with Venezuela’s Teachers Federation.
US prosecutors charged Saab in connection with a bribery scheme linked to Venezuela’s state-controlled exchange rate.