SANTO DOMINGO, DOMINICAN REPUBLIC (AFP) - Frenchman Christophe Naudin was sentenced on Thursday (Oct 27) to five years in prison for helping two French pilots involved in the "Air Cocaine" drug-smuggling case to escape justice in the Dominican Republic.

Naudin, a criminologist and aviation security expert, was convicted of criminal conspiracy and violation of the drugs law for helping pilots Pascal Fauret and Bruno Odos flee to France after they were sentenced to 20 years for drug trafficking, according to the verdict of Judge Jose Alejandro Vargas.

The verdict validates an agreement between the defence and the Dominican Public Prosecutor's Office under which Naudin had agreed to plead guilty, spend five years in prison and to pay the Dominican state a US$33,000 (S$45,195.64) fine.

Naudin was ordered to serve his sentence in Najayo prison, near Santo Domingo, where he has been detained since March 2016 after his extradition from Egypt.

Pilots Fauret and Odos, who maintain their innocence, were arrested in March 2013 as they were about to depart for France in a private jet found to be carrying 680 kilograms of cocaine.

Following their conviction, they somehow managed to flee after they were released pending an appeal - an escape that Dominican prosecutors said Naudin facilitated.

Fauret and Odos fled back to France vowing to clear their names, but were rearrested in November 2015 near the French city of Lyon.

Paris has ruled out extraditing them.

Two other Frenchmen, Nicolas Pisapia and Alain Castany, who were passengers when the cocaine was discovered, are still in the Dominican Republic, where they were sentenced on appeal in 2016 to 20 years in prison.

The affair has prompted keen interest in France, after Interpol issued arrest warrants for Fauret and Odos, as well as a far-right member of the European Parliament accused of involvement.