"What did my son do till he was beaten up so badly?"

Amir Ahmad, 47, just could not justify the tragedy that befell his son.

His son, Muhammad Anas, a Form Two student, was allegedly assaulted by three seniors of his school in Sungai Petani, Kedah on Sunday.

Amir said he was made to understand that his son was beaten up and had his head slammed against the wall in the 10am incident, leading him to sustain serious head injuries.

He said the incident happened after a teacher asked Muhammad Anas to call in a classmate into the classroom.

"He said the teacher asked him to call in the kids, and so he pulled one of the kids' hand... the kid was his classmate.

"Coincidentally, the kid's brother saw it and thought my son was trying to cause harm. That's how it all started.

"After that, the kid's brother and two others started punching him and banged his head against the wall," said Amir.

The victim also told his mother, Suriyati Che Said, 47, about the incident at about 3pm yesterday after experiencing headache.

Amir said his son vomitted when they were on their way to the Sultan Abdul Halim Hospital in Sungai Petani, at about 4pm.

He said an x-ray showed signs of internal bleeding inside his son's head.

Muhammad Anas is currently being treated at the intensive care unit of the Sultanah Bahiyah Hospital here.

"I leave it to the police. I am very disappointed, I hope it doesn't happen to other children," Amir said, adding that he has also informed the school about the incident.

Meanwhile, Kuala Muda district police chief, ACP Md Zukir Md Isa confirmed the incident.

Police have also detained four male students, all aged 15.

The case is being investigated under Section 325 of the Penal Code for voluntarily causing grievous hurt.