PALERMO, Italy (Reuters) - The eldest sister of late Sicilian Mafia boss Matteo Messina Denaro has been sentenced to 14 years in prison for aggravated mafia association and receiving stolen goods, a judicial source said on Thursday.

Messina Denaro was Italy's most wanted man until his arrest in January last year. He had spent three decades on the run, during which he was judged guilty of multiple murders, and died of cancer last September.

His sister Rosalia was arrested in March 2023, and put on trial as prosecutors accused her of covering up for her fugitive brother, managing his finances and helping him liaise with the outside world.

The 69-year-old woman was convicted in a first instance ruling in Palermo, the capital of Sicily. According to Italian law the verdict can be appealed twice before becoming final.

While on the run, Messina Denaro followed mafia tradition in communicating with relatives and affiliates via "pizzini", small pieces of paper with orders and instructions, sometimes written in code. Police found some of them in his sister's home.

The mobster went into hiding in 1993 as a growing number of turncoats started providing details of his involvement in mafia crimes, including helping plan the 1992 murders of anti-mafia prosecutors Giovanni Falcone and Paolo Borsellino.

Nicknamed "U Siccu" (The Skinny One), Messina Denaro was the son of a mafioso and a close ally of the Corleonesi led by Salvatore "the Beast" Riina, who became the undisputed "boss of bosses" of "Cosa Nostra", the Sicilian mob.

(Reporting by Wladimiro Pantaleone; writing by Angelo Amante, editing by Alvise Armellini and Keith Weir)