A Catholic nun was among a group of 25 people arrested by Italian police on Thursday on suspicion of being part of a mafia network engaged in extortion and drug trafficking.

Prosecutors alleged that Sister Anna Donelli took advantage of her role as a prison volunteer to act as a contact between jailed members of the ‘Ndrangheta mafia and gang members on the outside.

The 57-year-old volunteered at San Vittore prison in Milan and earlier this year won a civic award for her work in jails and some of the more deprived areas of the city.