Exhausted and dishevelled, several hundred Nigerian schoolboys seized in a mass abduction claimed by Boko Haram experienced their first full day of freedom on Friday after a nearly week-long ordeal.
But relief at their survival mingled with concern that many others could still be captive, and the circumstances of their release remained unclear.
Looking dirty, worn-out and distraught, and most of them without shoes, the boys were brought to the governor's office in Katsina, the capital of Katsina state in northwestern Nigeria, after being released late Thursday.
One boy broke down in tears as he was being led into the hall for the reception by state governor Bello Masari. An official took a handkerchief and wiped the tears.
"I am happy, very happy that I will see my father, mother and junior brothers," said another, 14-year-old Ibrahim Sani, smiling but looking tired.
The boys were then reunited with their parents.
Hajia Bilikis, a mother who has been waiting anxiously with other parents, spoke of her exultation when she caught sight of her boy, Abdullahi Abdu-Rasaq, 15.
"I'm so excited... I have to cry, the cry of joy when I saw him," she told AFP.
Governor Masari said the youngsters had been traumatised by what their experience.
"You suffered physically, mentally and psychologically, but let me assure you that we suffered more and your parents suffered more."
The boys were given new clothes before they were received also in the governor's office by President Muhammadu Buhari, who spoke in Hausa, a language widely used in northern Nigeria.
- Jihadists' claim -
The mass assault last Friday by armed men on a rural school in Kankara was initially blamed on criminal gangs who have terrorised the region for years.
But on Tuesday Boko Haram, the brutal jihadist group behind the abduction of 276 schoolgirls in Chibok in 2014, claimed responsibility.
Local officials announced late Thursday that the boys had been released and would spend the night in the protection of security agents.
A security source, speaking on condition of anonymity, said they had been left in the forest after negotiations between the authorities and the abductors, but gave no further details.
"This is a huge relief to the entire country & international community," Buhari said on Twitter.
It remained unclear, however, if all the abducted schoolboys had been released, amid ongoing uncertainty over the number taken in the first place.
UN chief Antonio Guterres called "for the immediate and unconditional release of those who remain abducted" while commending the rescue of "some of them".
He urged Nigeria to make "increased efforts to safeguard schools and educational facilities in the country".
In an interview with state channel NTA late Thursday, Masari said: "I think we have recovered most of the boys, it's not all of them."
In a video released by Boko Haram Thursday, a distressed teenager said he was among 520 students kidnapped.
- 'Bandits and terrorists' -
Sources had told AFP that the raid was carried out by a well-known criminal in the region, Awwalun Daudawa, in collaboration with Idi Minorti and Dankarami, two other crime chiefs with strong local followings, acting on behalf of Boko Haram.
Experts have warned that jihadists -- operating in the northeast of the country, hundreds of kilometres (miles) from where Friday's attack occurred -- were attempting to forge an alliance with criminal gangs in the northwest.
Buhari's official spokesman Garba Shehu said on Twitter "the northwest now presents a challenge which his administration is determined to deal with."
"It is unfortunate that the bandits and terrorists continue to get weapons even under the circumstances of the border closure. We are going to dare them."
Many parents of the missing students said they had long feared an attack, given escalating violence in the region.
"Our children told us armed men would come up to the school fence but they never breached the fence... until last Friday," said Hauwa'u Isah, mother of an abducted child.
Around 8,000 people have been killed in the northwest since 2011, according to the International Crisis Group (ICG) think tank.
#BringBackOurBoys started trending on social media earlier this week, in reference to a similar hashtag after the Chibok kidnappings.
Small protests to push for the boys' release took place in Katsina on Thursday as Buhari was visiting the state.
Bilikis, the mother, vowed on Friday never to let her lad live in a boarding school again.
"Kankara is not safe. There have been a lot of kidnappings before," she said.