(ANSA) - Palermo, November 13 - Three people have been arrested as part of an investigation by prosecutors in Palermo on an international drug trafficking ring allegedly operating on behalf of the Sicilian Mafia and fugitive Cosa Nostra boss Matteo Messina Denaro, investigative sources said Wednesday.

ROS security Carabinieri police from Trapani and GICO economic-financial police in Palermo carried out the nationwide operation on Wednesday that led to the arrests and included search operations in which 100 Carabinieri and tax police officers were deployed, the sources said.

Police said Meddina Denaro, called Iddu (Him) by his subordinates, may have been driven to Trapani rail station recently by one of the three people arrested.

Police have been 'draining the swamp' of Messina Denaro's protectors and abetters for years.

In June the latest 19 people were placed under investigation in a fresh probe into persons believed to be helping Cosa Nostra's No. 1 fugitive evade capture.

The 19 are professionals and 'men of honour' who have already been involved in previous probes, police said.

In the last few years police have made a series of sweeps snuffing out the superboss's web of supporters including close relatives - two brothers in law are doing hard time - and businessmen who, according to investigators, have funded his life on the run.

These include electrician-turned-windfarm king Vito Nicastri who is accused of bribing former League transport undersecretary Armando Siri for an amendment, which was never approved, in favour of renewable energy projects.

Nicastri got nine years in jail for mafia association last month.

In the latest operation, police carried out raids at Castelvetrano, Mazara del Vallo, Partanna and Campobello di Mazara in western Sicily.

Messina Denaro, 57, has been on the run since 1993 and was once considered a candidate to be Cosa Nostra's boss of bosses following the deaths of Bernardo Provenzano in 2016 and Salvatore Riina in 2017.

He is on Europol's list of Europe's most wanted fugitives.

He has not been seen in public in 23 years.

An informant in 2014 helped authorities update their facial composite of him.

