GENOA, Italy (Reuters) - Italian prosecutors have placed around 40 more people under investigation in relation to the collapse of a motorway bridge in Genoa last year, including ex-officials of Atlantia’s units and the transport ministry, judicial sources said.

FILE PHOTO: The collapsed Morandi Bridge is seen in the Italian port city of Genoa, Italy August 15, 2018. REUTERS/Stefano Rellandini

Former officials at state-controlled road maintenance operator Anas were also under investigation, the sources said.

The prosecutors’ move broadens a probe started last year after a section of the Morandi bridge in the northern city of Genoa collapsed, sending dozens of cars plunging to the ground and killing 43 people.

The bridge is part of the A10 motorway, which links Genoa to the French border and is managed by toll-road operator Autostrade, a unit of infrastructure group Atlantia.

The 40 or so additional suspects - from Atlantia units Autostrade and Spea Engineering - join Atlantia CEO Giovanni Castellucci, Chairman Fabio Cerchiai and another 19 officials at both the infrastructure group and the transport ministry who were placed under investigation last year.

Atlantia and Anas declined to comment on Thursday.

“The ministry is calmly waiting on the prosecutors’ work, while ensuring full cooperation to get at the complete truth,” a spokesman for the transport ministry said.

Prosecutors will ask the judge for a new evidentiary hearing on the disaster to ascertain the causes of the collapse, the head of the prosecutor’s office Franco Cozzi said recently.

The hearing is expected to last several months, he added.

Autostrade, which has come under fire from Italy’s government for the disaster, has repeatedly said that it had carried out checks on the bridge as required by law.

Under Italian rules, the motorway operator is responsible for maintenance, while the ministry has a supervisory role.