Niger has detained and charged 643 people since February for their links to the Nigerian Islamist group Boko Haram, Security Minister Hassoumi Massaoudou told parliament.
Niger has deployed 3,000 soldiers to a joint regional force formed with Chad, Cameroon and Nigeria in order to quash the Boko Haram insurgency, in which thousands have been killed.
Several Boko Haram networks and sleeper cells have been dismantled in Niger's southern Diffa region, which is on the border with Nigeria, since a state of emergency was declared there in February and troops deployed, Massaoudou said.
"If this measure had not been taken, we could have had an uprising in the very interior of Diffa,'' the minister told parliament late on Tuesday.
Those arrested and detained have been charged with acts of terrorism and criminal conspiracy, he said.
Diffa came under heavy attack in February when Boko Haram, which wants to establish an emirate in northern Nigeria carried out attacks in neighboring countries.
Boko Haram, which loosely translates as "Western education is sinful'' in the northern Hausa language, began an insurgency in 2009 to establish a state adhering to strict sharia law.
The group controlled an area roughly the size of Belgium at the start of the year but has since been beaten back by Nigerian troops, backed by Chad, Niger and Cameroon.
Lawmakers also voted on Tuesday to extend the state of emergency in Diffa by three months.
