Nigerian prosecutors have charged five high-ranking officials, including three former ministers, with corruption for allegedly accepting bribes.
Three former government ministers, a top interior ministry bureaucrat and a former high-ranking ruling-party official pleaded not guilty to corruption charges as their trial got under way in Abuja's High Court.
A Nigerian businessman also charged in the case was not present.
The five officials are charged with 16 counts of corrupt and false enrichment. They allegedly received bribes totaling more than $2 million from the French communications giant Sagem.
The French company was awarded a more than $200 million contract several years ago to produce Nigerian national identity cards.
Former Labor Minister Hussain Akwanga, who is among the accused, was fired earlier this month when the scandal was first reported. The two other former ministers were no longer in top government positions.
If found guilty, they all face between five- and seven-year jail terms. A judge also said they will be denied bail.
The trial is seen as a test case for Nigeria's Independent Corrupt Practices Commission, which was set up by the government three years ago. The opposition has accused this commission of being incompetent, as it has yet to secure the conviction of a single senior official, despite reports of ongoing corruption at very high levels of government.
Oil-rich, but impoverished, Nigeria is often viewed as one of the world's most corrupt countries.