There should be a helper
According to Mr Wong Ann Lin, the Chairman of the Singapore School Transport Association, there should have been an attendant at the back of the bus to watch over the children.
"School buses have regulations and standards that have to be followed," he said. "There should be no reason not to have an attendant at the back of the bus, especially for younger children still in kindergarten."
For buses ferrying children who are at least primary school age, an attendant is required if it is authorised to carry more than 30 children.
But for kindergarten school buses, an attendant is required whatever the size of the size of the bus.
A spokesman from the Singapore School and Private Hire Bus Owners' Association also said that bus drivers should check their bus before leaving for a break.
According to the Land Transport Authority's website on the safety requirements for school buses, first-time offenders can be fined up to $1,000, or be jailed up to three months.
Repeat offenders can be fined a maximum of $2,000, or be jailed up to six months.