He said the deaths were presumably caused by other reasons because they died at the same time.

“We have ordered the director-general of the Department of Corrections, Pol Colonel Naras Savestanan, to investigate other issues, such as conflict in the prison,” he said. “According to academic information, having toxic goiter cannot cause people to die easily.”

He added that the low potassium level could also be caused by other reasons, such as taking drugs or drinking alcohol. Therefore, they cannot conclude that toxic goiter had caused the deaths.

“The investigation in medical terms, such as blood tests, takes only one week to see the results. Also, another issue — violence among the inmates — is not a big problem for us,” he added.

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