Nigerian gunmen have freed scores of students abducted from three schools in the northwest this year, officials said Friday, following a burst of sudden releases.

The mass abductions were part of a string of kidnapping for ransom attacks on Nigerian schools and colleges this year by heavily armed gangs known locally as bandits.

Nearly 100 pupils abducted from an Islamic seminary in Tegina, Niger State were reunited with their families on Friday after three months in captivity.

Wearing blue headscarves and tunics, the male and female students, some younger than 10 years old, were met by the state governor and their families.

Nigerian schoolchildren kidnapped from an Islamic seminary three months ago have been reunited with their parents
Nigerian schoolchildren kidnapped from an Islamic seminary three months ago have been reunited with their parents AFP / John OKUNYOMIH

"I have a child and I am very happy. I give God all the glory," said one father Fasilat Jimoh Danjuma. "Thank God they are back hale and healthy and we are happy."

During the Tegina seminary kidnapping on May 30, around 200 motorcycle-riding gunmen stormed the town in Niger State's Rafi district before transporting the pupils to a rural hideout.

School officials said one pupil had died during captivity.

In a separate case, gunmen also released 32 more students kidnapped in July from a Baptist school in northwest Kaduna state, a church leader and family representative said on Friday.

Nigerian schoolchildren kidnapped from an Islamic seminary three months ago have been reunited with their parents
Nigerian schoolchildren kidnapped from an Islamic seminary three months ago have been reunited with their parents AFP / John OKUNYOMIH

A gang had snatched more than 100 students from the Baptist school, and since then dozens have been freed or escaped.

"The bandits released 32 more of the students today, Friday. We still have 31 in captivity and we have hope they will be released soon," Reverend Joseph Hayab, a representative for the families, told AFP.

"As with previous students, we had to pay ransom to have them freed but I don't want to reveal the amount."

In neighbouring Zamfara State, another 18 students and staff were taken from an agriculture college earlier this month were also freed, state police said.

Nigeria's northwest and central states have been caught up in a surge in violence from heavily armed criminal gangs who loot villages, steal cattle and carry out mass kidnappings.

The violence has its roots in years-long tensions and tit-for-tat raids between farmers and nomadic herders over grazing land and water resources.

President Muhammadu Buhari has ordered military operations and air strikes on bandit camps but attacks have not stopped. Some local governors have attempted amnesty deals with the bandits but most have failed.