MOSCOW — Three veteran Maltese criminals linked to a failed bank robbery and other crimes have been charged with the car-bomb killing of Daphne Caruana Galizia, Malta’s best-known journalist, whose exposés of corruption in high places infuriated the Mediterranean island’s political and business elite.

The suspects, who appeared late Tuesday in court in Valletta, Malta’s capital, pleaded not guilty to charges that included murder and illegal possession of explosive material, according to local news media reports. All aged over 50, they were arrested on Monday, along with seven other known criminals who have since been released.

The arrests, which came just three days after a fact-finding team sent by the European Parliament voiced skepticism about Malta’s ability to solve the murder, were the first outward sign that the authorities were any closer to finding those responsible.

It remains unclear, however, whether the investigation, which is being assisted by the F.B.I. and European police officers, has made any progress in identifying who ultimately ordered Ms. Caruana Galizia’s killing.