Tokyo, Jun 3 (IANS): A missing seven-year-old boy was found alive and unharmed after searchers spent nearly a week combing dense forest in Japan's Hokkaido island, officials said on Friday.

Yamato Tanooka was discovered in a small building at a military exercise ground about 4 km from the spot where he was left alone on May 28 at the roadside for a short time by his parents for being naughty, CNN reported.

Takayuki Tanooka, the father of the boy, said he was "very sorry" for what happened to his son and regretted the punishment.

"I told my son that I am sorry that I made him go through a very hard situation," Tanooka told Asahi TV on Friday after being reunited with his son.

"I never thought the situation would develop in such a way. I thought it would be good for him, but it was too much," he added.

Japan's Self-Defence Forces personnel found Yamato on the premises of the military's Kamagatame exercise field early Friday morning, said Satoshi Saito, a spokesperson for the local fire department.

An SDF member who found the boy said he was hungry. The member gave him water and a rice ball.

The boy told police he reached the building the first night he was missing, local media said.

He appeared to be in good condition for someone who had spent seven days without food, Yoshiyuki Sakai, the doctor who examined Yamato, said.