(CNN) -- The American held in North Korea, Matthew Miller, begins his six-year sentence of hard labor on Thursday. A North Korean government official released a photo of Miller, taken on Wednesday. Dressed in a blue-gray prison garment with the number 107 and his head shaved, Miller is seen with his eyes downcast, staring away from the camera. Details about where he'll serve his sentence or what labor he will be required to do were not released. Miller was convicted of committing "acts hostile" to North Korea and sentenced earlier this month. North Korea has accused him of ripping up his visa on arrival to the country so he could go to prison and expose human rights violations there, according to the state-run Korean Central News Agency.
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American Matthew Miller begins six-year sentence of hard labor Thursday
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North Korea released photo of Miller in prison wear
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Miller was convicted of committing "acts hostile" to North Korea
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Miller called his family to ask for help on Wednesday
He has also written a letter imploring @placeholder officials for help.