Disabled teenager found with human BITE MARKS on her body is unable to name her attacker because she cannot speak

• Cerebral palsy sufferer's family say fellow student is to blame for attack
• Philadelphia school blames 16-year-old's sister for inflicting the wounds

By Jessica Jerreat

Published: 18:43 EDT, 18 May 2013 | Updated: 21:52 EDT, 18 May 2013

A 16-year-old cerebral palsy sufferer who was bitten on her arm and shoulder is unable to tell her parents who is responsible for the brutal attack because she cannot speak.

When Ariel Alexander's parents reported the bite marks on their disabled daughter to her special needs school in Philadelphia, the school tried to blame the attack on Ariel's sister.

Her parents have rejected claims that the attack happened in their own home, questioning how Ariel's attack went unnoticed in the special needs classroom of Martin Luther King High School.

Victim: Cerebral palsy sufferer Ariel Alexander is covered in bite marks but she cannot name her attacker

Brutal attack: Human bite marks can be clearly seen on the disabled teenager's back and shoulder

Ariel's family believe the attack happened in school on May 1, telling MyFoxPhilly.com they first noticed the marks two days later.

The teenager, who has been confined to a wheelchair for most of her life and is unable to communicate clearly, had four human bite marks and other marks along her shoulder and back.

'It's brutal! It is brutal,' Mr Alexander said. 'There's no way possible that no one's seen the incident occur.'

He claims that after reporting the attack to her school, a male teacher told them that one of Ariel's classmates was responsible. 

Mr Alexander added that the teacher suggested one of the other pupils who has special needs had been attacking other students.

Silenced: Randell Alexander with his daughter Ariel, who is unable to communicate and name her attacker

The school rejects this claim however, saying that when the teachers were interviewed they denied seeing the attack.

Fernando Gallard, a spokesman for the school district, said: 'It could not have happened at school, and if it could have -- if for some reason something happened-- someone would have seen it.'

Ariel, whose suffers from a neurological disorder that affects muscle movements, shares a special needs classroom with six other children and seven adult supervisors. 

While many toddlers go through a phase of biting, it is also often seen in older children who have development problems or disabilities.

The school reported the injuries to Philadelphia's Department of Human Services, which is investigating the case as possible child abuse.

Blame game: Ariel's parents say the attack happened at Martin Luther King High School, but teachers deny this

Mr Alexander said the department interviewed him and his wife about the possibility that Ariel's 17-year-old sister had bitten her.

Cerebral palsy is one of the most common disabilities affecting muscle movement in the U.S. The Centers for Disease Control and Prevention estimates that one in every 303 American eight-year-olds are affected by it.

After research in 2006, the center concluded that families and sufferers were in need of improved health, education and intervention services.

Cerebral palsy sufferers can be affected to differing degrees. While some, like Ariel, are confined to wheelchairs and lack the ability to speak clearly, others may be only slightly affected and will need little assistance over their lives.

And while there is no cure, researchers say that with early intervention for physical and occupational therapy, many sufferers are able to lead regular lives.

But in Ariel's case, with no clear way to tell her parents or teachers who caused her wounds, her attacker remains unnamed.

Investigators from the Department of Human Services are due to return to the family's home next week to check on the welfare of the Alexander children.