A court on the Indian Ocean island of Mauritius on Friday sentenced a French woman convicted of drug smuggling to 20 years in prison.

Aurore Gros-Coissy, 27, was arrested in 2011 with 1,680 Subutex tablets, a drug sold on prescription in France as a heroin substitute for those trying to end their addiction, but banned in Mauritius.

She has always maintained her innocence, claiming the drugs were placed there by a friend, whose mother, Mauritian national Giantee Ramchurn, was also sentenced to 20 years in jail on Friday.

Judge Bobby Madhub also fined Gros-Coissy 1,300 euros and Ramchurn some 2,600 euros.

Both had been found guilty in November last year.

As well as Gros-Coissy, four other French nationals have been jailed in Mauritius for smuggling Subutex and are serving prison terms ranging from 15 to 20 years.