The truck driver set off the explosives when going through the second security check procedure after the security personnel had already found something suspicious about the truck.
The massive blast severely damaged the checkpoint and caused heavy casualties, said Iraqi authorities.
Roads around the explosion site have reopened, but the clean-up will take a few more hours to finish, said Saleh.
The second explosion of a fuel tanker, which was caused by the blast, was reportedly a factor in the number of heavy casualties.
Babil Governorate provincial authorities have formed an investigation group to trace the truck’s travel route and have announced a three-day memorial service for the victims of the attack.
Iraqi President Fuad Masum condemned the attack on Sunday, urging security forces to bring the perpetrators to justice as soon as possible.