In a court case that ended last month, sisters Francesca and Elisabetta Grillo were cleared of defrauding Lawson and her ex-husband Charles Saatchi of £685,000 (€830,000).
Michele Grillo, 66, was taken into custody on Wednesday after a long investigation into the criminal activities of the Barbaro-Papalia mafia clan, which is based in the small town of Plati, southern Italy.
Judicial sources confirmed yesterday that Grillo was the father of Elisabetta and Francesca. There was no suggestion the daughters had any link to Grillo’s case.
In the Lawson trial, the sisters argued there had been an understanding that they could spend at will on credit cards if they kept quiet on the chef’s drug-taking.
Lawson admitted during the trial that she had taken cocaine several times and said she had smoked pot occasionally in the final year of her marriage to art dealer Saatchi.
A well-known TV star and author in Britain and the US, Lawson has been nicknamed the ‘Domestic Goddess’ after the title of one of her best-selling cook books.
The Calabrian mafia, known as the ‘Ndrangheta, has in recent years eclipsed the power of its more storied cousin, the Sicilian mafia or Cosa Nostra, thanks to its key role in importing cocaine from South America to Europe.
Grillo is accused of conspiracy to sell “large” amounts of cocaine and hash and extorting €85,000 from the owner of a petrol station, according to the 196-page warrant for his arrest.
He also helped suppress evidence needed in criminal trials involving men allegedly tied to the clan, the warrant said.
Grillo, a truck driver, had been under surveillance since 2011 and is considered to be right-hand man to Agostino Catanzariti, also arrested on Wednesday, and whom police consider to be a high-level clan leader.
Grillo previously served 15 years behind bars from 1981 for kidnapping and holding for ransom Tullia Kauten, owner of a designer fashion store in Milan.