Gunmen on Monday seized an unspecified number of primary school pupils and teachers in the northwestern Nigerian state of Kaduna, the government said, in a region wracked by banditry and kidnapping.

The raid is the latest in a string of attacks on schools in Nigeria, coming just four days after 39 college students were kidnapped by a gang.

Kaduna's home affairs commissioner, Samuel Aruwan, said the government had received security reports that "some pupils and teachers" had been abducted at the LEA Primary School in Rema, in the Birnin Gwari area.

The authorities are "currently obtaining details on the actual number of pupils and teachers reported to have been kidnapped," he said in a statement. 

The total number of children enrolled at the school was not immediately known. Most primary pupils in Nigeria are aged between six and 11.

Gangs in northwest and central Nigeria, who are known locally as bandits, have recently turned their focus to mass kidnappings, seizing school students for ransom.

At least four mass kidnappings have occurred since December.

Gunmen abducted 39 students late Thursday from hostels on the outskirts of  Kaduna city, the state capital.

On Monday, the authorities shut down their college and sent home 180 other students and staff who had been rescued.

"Yesterday, under the cover of the military, we brought all the students back to the school so they could pick all their personal belongings before we handed them over to their parents," Abubakar Hassan, head of Kaduna's State Emergency Agency (SEMA), told AFP.

"Parents have been asking these students to be released to them and they would have been released earlier but we needed to manage their trauma and get them to a certain level of comfort," he added.

At the weekend, security forces thwarted a gang that had stormed a secondary school in Ikara, Aruwan said on Sunday.