MILAN - A bus full of school children was set on fire by its driver in the outskirts of Milan on Wednesday in an apparent protest against migrant drownings in the Mediterranean, Italian authorities said.All the children managed to escape unhurt before the bus was engulfed in flames. Police said the driver was an Italian of Senegalese origin."He shouted, 'Stop the deaths at sea, I'll carry out a massacre,'" spokesman Marco Palmieri quoted the driver as telling police after his arrest.A video posted on Italian news sites showed the driver ramming the bus into cars on a provincial highway before the fire took hold. Children can be seen running away from the vehicle screaming and shouting "escape."One of the children told reporters that the driver had threatened to pour petrol on them and set them alight. One of group managed to call the police, who rushed to the scene and got everyone to safety.Palmieri said some children were taken to hospital as a precautionary measure because they had bruises or were in a state of shock, but none suffered serious injuries.The United Nations estimates that some 2,297 migrants drowned or went missing in the Mediterranean in 2018 as they tried to reach Europe.A Libyan security official said on Tuesday that at least 10 migrants died when their boat sank off the Libyan coast near the western town of Sabratha.