Two final year students of the Edo State School of Nursing, Benin, Edo state in Nigeria, have been arrested for allegedly sexually assaulting a six-year-old girl.

It was alleged that three students, one of whom is still on the run, had raped the child after luring her into their hostel room, The Nation reports.

The accused reportedly tied the girl's limbs and defiled her.

Her mother, who does petty trading in front of the school, had gone to the market at the time.

The woman claims she noticed that her daughter was stooling and urinating with semen coming out of her anus and reported the case to the Commissioner for Health.

According to the school’s Principal, Mabel Omobude, an investigation started after the victim's mother wrote a letter to the Commissioner.

She (the mother) wrote a letter to the Commissioner of Health, which was sent to my director to investigate," Omobude said.

"That was on Thursday. We have started our investigation.”

Police spokesman, DSP Stephen Onwochei, said a proper case of defilement has not been filed, adding that the accused claim the allegations are false.

“That matter is not too straightforward. The little we know is that on May 15, the mother of the girl, who sells at the school, had a problem with some student-nurses because they asked her to pack out of the shop.

“Later, on May 16, she reported to the school that something of that nature (defilement) happened.

"But she did not report to the police, in the first instance.

"So, it was later that the lawyer to the accused wrote a petition to the Area Commander that someone was trying to tarnish his clients’ image."

A non-governmental organisation (NGO), Child Protection Network, has taken up the case.

The group's coordinator, Jennifer Ero, reportedly said the school's authorities tried to cover up the matter, threatening to eject the victim’s mother.

"We will ensure that this matter is charged to court.

"We will ensure justice for this child and make sure she goes through counselling.

"The girl is now restless. They activated the hormone that relate to sex. She does not behave well.

"It is a life-time damage they have done to this child."

“It’s because she was too small. It (the alleged act) affected her womb. She started stooling and urinating profusely. But she’s on treatment now."

The police are still investigating the incident.