More than 300 young men have been freed from a second Nigerian Islamic boarding school where they were chained up and raped, following a similar raid last month.

Police descended on the school in Daura in the northern Katsina state after some of the men managed to escape on Sunday and poured into the streets in protest.

The men were shackled and tortured at the school where they had been enrolled by their families to learn the Koran. Many had also been sent there to be treated for drug addiction.

The news comes after nearly 500 men and young boys were freed from an Islamic boarding school in Kaduna, around 280 miles south of Daura, where students had been chained, hung from the ceiling and beaten, authorities said.

Men and boys are pictured after being rescued by police in Sabon Garin, in Daura local government area of Katsina state on Monday

People with chained legs are pictured after being rescued by police in Sabon Garin, in Daura local government area of Katsina state, Nigeria October 14

'We learnt that the inmates here are over 300 and because of the inhuman treatments they are being subjected to they revolted yesterday (Sunday),' Katsina police chief Sanusi Buba said.

'Some of the inmates escaped while...about 60 of them stayed back,' he said, with most of them found in chains.

Buba said the school was established by 78-year-old Muslim cleric, Bello Mai Almajirai, 40 years ago. He later transferred management of the school to his son.

He said the school enrolled students brought by their families to learn the Koran and be treated for drug addiction and other ailments.

Daura which lies 45 miles from the state capital and near the border with Niger, is the hometown of President Muhammadu Buhari.

The students are from 'various parts of Nigeria', including Katsina state and neighbouring Niger Republic, said the police chief.

People are pictured after being rescued by police in Sabon Garin yesterday

Young men stand within the Islamic boarding after being rescued by police on Monday

According to Buba, the abused inmates were 'subjected to inhuman conditions,' with some of the students revealing that they were sodomised by their teachers.

Police will liaise with the state government to establish the identities of the young men and contact their families to return them home, he said.

Buba promised to arrest the proprietor and his teachers who managed to escape during the raid but will 'face the full wrath of the law'.

On September 26, in nearby Kaduna state, police discovered nearly 500 men and young boys standing in rows wearing ankle shackles, while others had their hands chained. Other photos show the torture victims with horrific scars on their backs.

One victim even claimed that previous students had died from being tortured.

Parents have since been reunited with some of the children rescued by police at the Hajj transit camp.

The detainees in Kaduna state last month, most of them young boys, emerged with scars on their bodies after police raided the building

During the raid on the school in Kaduna last month, police said they found a 'torture chamber' where students were chained, hung and beaten

Some of the almost 500 male students of 'different nationalities' sit on the floor in chains outside the school's torture chamber in the Rigasa area of Kaduna in northern Nigeria

Some of the male students are pictured after being rescued by police from an Islamic school in Kaduna state where they were tortured and raped

Police said the detainees were from Burkina Faso, Mali and other African countries.

The victims, including adults and minors, were kept in 'the most debasing and inhuman conditions in the name of teaching them the Koran and reforming them', Kaduna state police spokesman Yakubu Sabo said.

Bello Hamza, 42, told The Nigerian Tribune: 'I have spent three months here with chains on my legs. I am supposed to be pursuing my Masters in University Pretoria South Africa. I got admission to study Applied Mathematics, but here I am chained.

'They claim to be teaching us Quran and Islam, but they do a lot of things here. They subject the younger ones to homosexuality.

Some of the children rescued by police from captivity at a school wash up by a tank at the Hajj Transit camp in Kaduna, Nigeria on September 28

Some of the children rescued by poloce from captivity at aschool with strike marks on their backs, bathe at the Hajj transit camp in Kaduna, Nigeria on September 28

Police said last month the detainees were kept in 'the most debasing and inhuman conditions in the name of teaching them the Koran and reforming them'

'This is supposed to be an Islamic centre, but trying to run away from here attracts severe punishment; they tie people and hang them to the ceiling for that, but engaging in homosexuality attracts no punishment.'

Police had been tipped off by complaints from local residents who became suspicious of what was happening inside the school.

During the raid on the school, police said they found a 'torture chamber' where students were chained, hung and beaten.

A man stands with chains on his ankles and wrists. Private Islamic schools are common in mainly Muslim northern Nigeria, where government services are often lacking

Authorities said the freed captives will be given medical and psychological examinations

The proprietor of the school and six staff were arrested during the raid but he insists he did nothing wrong

The school, which has been operating for a decade, enrolled students brought by their families to learn the Koran and be rehabilitated from drug abuse and other illnesses, police said.

The proprietor of the school and six staff were arrested during the raid.

A high rate of drug use and lack of rehabilitation facilities in northern Nigeria are forcing parents to enrol their children in informal reformatory Islamic schools where they are subjected to abuses.