A father has told the BBC he felt powerless as he witnessed gunmen on motorbikes abduct dozens of children, including his son, after storming a Catholic boarding school in northern Nigeria in the early hours of Friday.

The father said he was asleep when he was awoken by the noise of the gunmen as they went past his home with the children they had seized from St Mary's school in Papiri village in Niger state.

"They [the children] were being trafficked on foot the way shepherds control their herds. Some children were falling and the men would kick them and instruct them to stand up.

"The gunmen were on about 50 motorcycle bikes while controlling them," said the father, whose name we have changed to Theo for his safety.

Speaking to the BBC in the dormitory where his son used to sleep, Theo said he was in no position to stop the abduction.

"I felt like going [to help] but I thought better of it. Even if I did go, what could I do? I couldn't do anything," he told the BBC, adding that he called the police but it was too late by the time they arrived.

The Christian Association of Nigeria has said that 303 students and 12 members of staff were abducted from the school, while 50 children managed to avoid being taken away and have been reunited with their families.

The school is run by the chairman of the association's Niger chapter, Bishop Bulus Bawa Yohanna, who has shared a list of those abducted with the BBC.

However, the police said they were only aware of a few children escaping on the night of the abduction.

The Niger state governor, Umar Bago, told local media that the number of abducted students had been exaggerated, and it was "far, far below" 303.

The governor blamed the school authorities for opening the establishment despite threats by unknown gunmen four years ago, and again two months ago.

"The schools in that area have been closed for four years now. I was surprised to learn the school is still open," Bago said.

He also insisted that the attack was just a "scare" and that all students would be rescued sooner or later.

The bishop said that no security agencies have been deployed in the community since the abductions.

Along with some other parents, Theo has been camping outside the school, angry with the government's response.

"Our children were kidnapped but the government doesn't seem to pay attention to it," said Theo.

He said he was frustrated that the state governor had not visited the school, and only went to a nearby community to speak to security agencies and local leaders.

"We have concluded that the government is not concerned about us - we feel like we are not part of the country, they have abandoned us."

The pain being endured by the parents of those children who are still missing is all too evident.

"I am sad, my whole life is filled with sadness," said a mother, whose son was among the children taken by the gunmen.

"He's my only son, he's my first-born, please help us," she said.

Another parent, Lucas, told the BBC that two of his children had been abducted, but the youngest one, a six-year-old boy, was lucky and managed to avoid falling into the clutches of the kidnappers.

"When I saw him, I was so excited. I called him by name, he turned and ran to me. I hugged and embraced him," he said.

The northern part of Niger where Papiri is located has recently become a hot-spot for kidnappings for ransom.

The payment of ransoms has been outlawed in an attempt to cut the supply of money to the criminal gangs, but to little effect.

The BBC team drove about 500km (310 miles) to Papiri from the Niger state's capital, Minna and was advised several times not to take certain routes and, for periods, was escorted by police.

Many blame the crisis on the size of the state. In terms of landmass, Niger is the largest state in Nigeria, and larger than European countries like Denmark and the Netherlands.

It also has a lot of forests, which criminal gangs, referred to locally as bandits, use as camps and routes to connect to other states in Nigeria, as well as neighbouring countries.

The abduction at the school was the third to hit Nigeria in a week.

Last Monday, more than 20 schoolgirls, who the BBC has been told are Muslim, were kidnapped from a boarding school in Kebbi state, which borders Niger.

A church was also attacked further south in Kwara state, with two people killed and dozens of worshippers abducted.

President Bola Tinubu cancelled his trip to the G20 summit, held in South Africa at the weekend, to deal with the crisis.

He posted on social media on Sunday that all the 38 worshippers abducted in Kwara state had been rescued.

"Let me be clear: I will not relent. Every Nigerian, in every state, has the right to safety - and under my watch, we will secure this nation and protect our people," Tinubu said.

The spate of abductions has forced the closure of many boarding schools across Nigeria, with parents rushing to collect their children.

The government is under pressure from US President Donald Trump, who warned earlier this month that he would send troops to Nigeria with "guns a-blazing" if it "continues to allow the killing of Christians" by Islamist militants.

The Nigerian government has said claims that Christians are being persecuted is "a gross misrepresentation of reality" as "terrorists attack all who reject their murderous ideology - Muslims, Christians and those of no faith alike".

While some kidnappings are carried out by Islamist militant groups, many are carried out for ransom by criminal gangs, highlighting the deep security crisis in the country.