The three men accused of 'road murder' and other lesser crimes worked for city authorities in Venice and the bus company which owned the crashed vehicle.
Italian authorities are investigating three people in connection to last week’s deadly bus crash in Mestre, near Venice, where 21 people - most of whom were foreign tourists - were killed and 15 more injured.
It’s the first big development in the probe launched following the fatal incident on 3 October, which is looking for those responsible for a crime that in Italy is called “road homicide” and it involves those who cause someone’s death by breaking road traffic rules.
The three accused of road homicides and other lesser crimes are two men who work for city authorities in Venice - Roberto di Bussolo and Alberto Cesaro - and another man who works as an administrator for La Linea, the company which owned the bus that crashed, Massimo Fiorese.
The first two men were responsible for overseeing the road system in Venice and its maintenance.
The bus, which was just a year old, crashed to the ground and landed upside down on the night of 3 October. The 40-year-old driver was among those killed.
The driver, who had an untarnished record, had just started his shift shuttling tourists from Piazzale Roma, at the edge of Venice's famed canals, to a four-star campground on the mainland offering bargain accommodation.
A video shows the city-owned bus disappear from the frame, as another larger bus travelling behind it continued along the elevated road. Prosecutors said the shuttle bus scraped against the guardrail for at least 50 metres before its fiery crash to a surface road opposite the Venetian borough of Mestre's train station.
The guardrail was bent to the pavement; the fence ripped open and the front of the bus was completely crushed.
Mayor Luigi Brugnaro initially said the incident was "inexplicable," though suspicions over the state of the road and its guardrail later emerged.