Shocking video shows grandpa dragging his grandson down the street

This is the shocking moment a grandfather hauls his 11-year-old grandson out from a classroom and beats him with a wooden chair in southwestern China's Sichuan.
Video footage shows the old man grabbing the young boy's hoodie and forcefully dragging him down through a flight of stairs as other schoolmates watch on.
Police were called to the scene where they arrested and detained the 'out of control' pensioner.The incident took place at Mingdexing Primary School, Yingshan city.
Primary school principal told qq.com that the grandfather came to punish his grandson as his son refused to give him money for medical treatment.
He hit the boy with a stool before dragging him down a flight of stairs.
The 11-year-old was hauled out from his classroom by his grandfather and dragged for about 400 ft.
The principal further explained that the grandfather had long cut off the relationship with the boy's father who works in another city.The young boy was brought up by his grandmother until she fell sick recently.
In addition to that, the old man was in need of money for a hernia surgery.
Teachers and security guards stopped the grandfather when he attempted to open the school gate.
Local policemen arrived on scene shortly afterwards and arrested the grandfather under China's Law on Public Security Administration Punishments.
He is facing an administrative detention for five to 10 days.