Police raided several premises in the Tuscan town of Lucca early on Thursday and detained team owner Luca Franceschi, former sports director Elso Frediani, pharmacist Andrea Bianchi and ex-trainer Michele Viola for allegedly supplying young riders with doping products.
Altopack was the team associated with the Velo Club Coppi Lunata with which 21-year-old Linas Rumsas competed before his death following a heart attack on May 2nd 2017.
"Since the young man, in the weeks leading up to his death, had obtained excellent placings in particularly tough races, far superior to those obtained in the past, the suspicion immediately arose that the sudden death was due to the use or abuse of unauthorized drugs," police told a press conference.
Suspicions were reinforced because his father, Lithuanian rider Raimondas Rumsas, along with his mother Edita, had in the past been investigated for trafficking doping substances.
"The investigation has revealed the existence of a real partnership aimed at facilitating doping practices," police said.
Franceschi "recruited the most promising cyclists, motivated them to take drugs and procured doping substances for them, including EPO [erythropoietin] in microdoses".
Franceschi's parents are also alleged to have allowed riders inject themselves at their home where doping paraphernalia including syringes, needles and powerful painkillers were found. Twenty-five vials of EPO were also discovered in the fridge at Viola's house.
All were placed under house arrest pending the conclusion of the investigation with a further 17 people being probed.
Police also searched the home of the father of the young deceased cyclist and his older brother, Raimondas Rumsas Junior, also a promising cyclist, who was suspended for four years last month for doping.
Rumsas's parents were at the centre of a doping investigation in 2003 when French customs officers seized a large quantity of doping products in Edita Rumsas's car on the day her husband finished third in the Tour de France.
Rumsas Senior tested positive for EPO at the 2003 Giro d'Italia and was suspended for one year.
Altopack is one of Italy's biggest amateur cycling teams and young athletes are said to have been encouraged to take banned products including EPO, growth hormone and opiate-based painkillers.
Searches were also carried out in other Tuscan towns, and the northern city of Bergamo.
Update, February 14th: The name of the cycling team has been adjusted to reflect Eppela did not have a relationship to the cycling team, other than a sponsorship arrangement which ended in October 2017.