NAKHON SAWAN: Police on Monday searched a military cadet tutorial school in downtown Muang district for evidence that could shed light on why a boy attending the school died last week.
The police sealed off a house which doubled as the tutorial school in tambon Wat Sai.
Accompanying the search team was provincial governor Atthaporn Singhawichai and provincial education office litigation officers.
The authorities were looking for clues into the death of Thapakorn Sapsin, 15. The boy reportedly died after suffering multiple injuries at the school last week. The injures suggested he had been hit with a hard object across his back and legs.
His family said they were not convinced Thapakorn's death was caused by "rugby-style antics" among friends, as claimed by the school head.
Pol Col Wathee Assawutmangkul, a spokesman of the Police General Hospital which conducted the autopsy on Thapakorn, said the boy sustained bleeding in the abdominal cavity and suffered trauma to some internal organs.
Nakhon Sawan provincial police chief, Pol Maj Gen Damrong Phetpong, on Monday said the search was also joined by representatives of related agencies as police needed more evidence to build a case in which no one has been charged so far.
A number of witnesses and fellow students at the tutorial school have provided investigators with statements. Pol Maj Gen Damrong said their accounts were useful.
He said if enough evidence can be gathered, arrest warrants will be issued.
Muang Nakhon Sawan police chief Suthinan Khongchamdee said investigators had spent three days quizzing witnesses, some of whom were initially reluctant to speak.
Natthapat Boonchuay, from the Nakhon Sawan education office, said there was no record of the tutorial school having applied for a licence.
If the school was operating illegally, its owner is liable for a prison term and a fine.