Parents of missing boy, 7, left in woods as punishment: 'We've done an unforgivable thing'

The parents of a Japanese boy left in the woods as punishment have expressed their remorse as the military joins the desperate search to find him.

"We have done an unforgivable thing to our child, and we have caused a lot of trouble for everyone," the boy's father, Takayuki Tanooka, told reporters. "I just hope he is safe."

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It has been five days since Yamato Tanooka was last seen. The child was visiting the mountains of northern Japan with his family when Hokkaido Prefectural Police say the boy's parents told him to get out the car as punishment for throwing stones at cars and people.

When Yamato's father returned minutes later, he was gone.

The boy's father told local Japanese-language reporters that they initially hesitated to alert authorities because of the circumstances.

"I couldn't bring myself to make the request [for the search] and give the reason [for him being missing] as it is because of a punishment," he said.

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The Japanese military has now joined the search for the boy, according to reports.

Hundreds of volunteers and police officers are already searching for the boy. Reuters reported that a local hunter is also expected to join the hunt after bear tracks were found close to where he was left.