ROME (Reuters) - Italian police on Tuesday said they had uncovered a gang of drug dealers testing a remote-controlled submarine which they were most likely planning to use for smuggling.

The organisation was based around the northern Italian city of Turin and was suspected of trafficking "significant amounts" of cocaine, hashish and marijuana, police said in a statement.

During the investigation, which ran between 2021 and 2022, police seized more than 204 kg (450 lb) of drugs. The small submarine, which the traffickers had designed and tested, was not yet operational.

There have been arrests, but police did not say how many. Nor did they say why they were announcing the investigation only now.

Police discovered the group, allegedly led by two Albanian brothers, following an investigation into car wash operators who were managing marijuana cultivations.

According to the statement, the smugglers were also operating in Ecuador, Belgium, France and Spain.

Police said the group used cars equipped with homemade double bottoms to smuggle cocaine, which also transited from Spain and France.

(Reporting by Angelo Amante; Editing by Nick Macfie)