The driver of a school bus in Italy was arrested on Wednesday after he allegedly set the vehicle, with several children inside it, on fire outside Milan, Reuters reported. All the children managed to escape before the bus burnt down.

According to Italian authorities, the driver set the bus ablaze to protest against migrant drownings in the Mediterranean Sea. “He shouted ‘Stop the deaths at sea, I’ll carry out a massacre’,” spokesperson Marco Palmieri quoted the driver as telling the police after his arrest. The driver was an Italian of Senegalese origin, said the police.

Twelve children and two adults were taken to hospital after suffering from smoke inhalation, The Guardian reported. Palmieri said they were taken to hospital as a precautionary measure and none of them had suffered serious injuries.

One of the children in the bus later told reporters that the driver had threatened to pour petrol on them and set them alight. A child managed to call the police, who rushed to the scene. After the police arrived, the driver allegedly doused the vehicle with an inflammable liquid and screamed, “Nobody gets off here alive.”

Italy’s Deputy Prime Minister Matteo Salvini said the police were searching the driver’s home, who had previously been jailed for drink driving and sexual assault. “I want to know why someone with similar precedents was driving a bus carrying children,” Salvini asked.

According to figures from the United Nations, around 2,297 migrants drowned or went missing in the Mediterranean Sea last year as they attempted to reach Europe.