At least 21 passengers, including two children, died after a bus crashed off a flyover near the Italian city of Venice and caught fire, media reports said.

According to reports, the bus was heading from Venice to nearby Marghera.

Four or five people are unaccounted for, officials told ANSA.

Police sources told ANSA that two children were among the victims and Veneto Governor Luca Zaia confirmed that minors were involved in the disaster.

Francesco Martino, chief of staff of the prefecture of Venice, told CNN that 18 people were also injured in the crash and that authorities were still trying to determine what caused it.

Reactions:

Italy's Prime Minister Giorgia Meloni expressed condolences and wrote on X: "I express my personal and the Government's deepest condolences for the serious accident that occurred in Mestre. Our thoughts go out to the victims and their family and friends. I am in close contact with the Mayor @LuigiBrugnaro  and with the Minister@Piantedosim  to follow the news on this tragedy."

Venice Mayor Luigi Brugnaro shared an image of the crashed bus and posted on X: "A huge tragedy struck our community this evening. I immediately ordered the city to mourn, in memory of the numerous victims who were on the crashed bus. An apocalyptic scene, there are no words."

EU Commission president Ursula von der Leyen said: "My deepest condolences to the families of the victims and those injured in the serious accident in Mestre."