ABUJA, Nigeria (AFP) — More than 130 schoolchildren seized by gunmen in a mass kidnapping in northwestern Nigeria earlier this month were released unharmed on Sunday, officials and the army said.

The kidnapping in Kuriga, Kaduna state on 7 March was one of the biggest such attacks in years and prompted a national outcry over insecurity.

Teachers and residents previously said around 280 pupils were kidnapped, but the army said 137 pupils were freed.

“The rescued hostages totalling 137 comprise of 76 females and 61 males. They were rescued in Zamfara State and would be conveyed and handed over to the Kaduna State Government for further action,” said army spokesperson Major General Edward Buba.

He told Agence France-Presse the number represented all the pupils who were in captivity. The numbers of those reported abducted in Nigeria are often lowered after people who went missing while fleeing attacks return home.

Press reports said the pupils were aged between eight and 15.

“The abducted Kuriga school children are released unharmed,” Kaduna state governor Uba Sani said in a statement that did not specify how they were freed.