In a statement read on public television, the government also announced that all those involved in trafficking migrants, many of whom pass through northern Niger on their way to Algeria or Libya, would be identified and "severely punished".
The decomposed bodies of 52 children, 33 women and seven men were found on Wednesday following their grisly death in October after two trucks carrying them broke down on the way to Algeria.
"This tragedy is the result of criminal activities led by all types of trafficking networks," government said as it announced the closure of the "ghettos", the name given to migrant camps in Agadez, the main town in northern Nigeria.
Prime Minister Brigi Rafini would pay a visit to the southern district of Kantche where most of the deceased came from, to present the "condolences of the nation wounded by this tragedy" to their families, according to the statement.