41 people died in the fire at the Le Constellation bar on New Year's Eve. More than 100 were injured.
Five local officials or former officials are being investigated as part of a wider criminal investigation. According to media reports, one of them is the town's mayor, Nicolas Féraud.
All five have had some form of responsibility for municipal security issues.
The bar had not had a fire safety inspection in years, and its owner is suspected of, among other things, causing deaths. A total of nine people are currently suspected of crimes.
