Sent appeal to President Obama, but never received a reply

The American who tore up his own tourist visa on landing in North Korea and demanded to be arrested so that he could experience prison life in the communist nation has been sentenced to six years hard labor for entering the country illegally to commit espionage.

Matthew Miller, 24, of Bakersfield, California, looked thin and pale at his trial in Pyongyang on Sunday, as he was handed out his sentence.

Miller, who looked thin and pale at the trial and was dressed completely in black, is one of three Americans now being held in North Korea.

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Sentenced: Matthew Miller, a U.S. citizen, sits on the dock at the Supreme Court during his trial in Pyongyang, North Korea, on Sunday

Showing no emotion throughout the proceedings, Miller waived the right to a lawyer and was handcuffed before being led from the courtroom after his sentencing.

The court, comprising a chief judge flanked by two 'people's assessors,' ruled it would not hear any appeals to its decision.

Earlier, it had been believed that Miller had sought asylum when he entered North Korea.

During the trial, however, the prosecution argued that was a ruse and that Miller also falsely claimed to have secret information about the U.S. military in South Korea on his iPad and iPod.

Miller was charged under Article 64 of the North Korean criminal code, which is for espionage and can carry a sentence of five to 10 years, though harsher punishments can be given for more serious cases.

Matthew Miller, a U.S. citizen, sits before the Supreme Court during his trial in Pyongyang

The Associated Press was allowed to attend the trial.

A trial is expected soon for one of the other Americans being held, Jeffrey Fowle, who entered the North as a tourist but was arrested in May for leaving a Bible at a sailor's club in the city of Chongjin.

The third American, Korean-American missionary Kenneth Bae, is serving out a 15-year sentence for alleged 'hostile acts.'

All three have appealed to the U.S. government to send a senior statesman to Pyongyang to intervene on their behalf.

During a brief interview with The Associated Press in Pyongyang last week, Miller said he had written a letter to President Barack Obama but had not received a reply.

Handcuffed Matthew Miller, a U.S. citizen, leaves after his trial at the Supreme Court in North Korea

Handcuffed Matthew Miller, a U.S. citizen, is led to a courtroom for his trial at the Supreme Court in Pyongyang

Fowle, a 56-year-old equipment operator for the city of Moraine, Ohio, said his wife, a hairstylist from Russia, made a written appeal on his behalf to Russian President Vladimir Putin.

He said the Russian government responded that it was watching the situation.

The U.S. has repeatedly offered to send its envoy for North Korean human rights issues, Robert King, to Pyongyang to seek the freedom of the detainees, but without success.

Former President Bill Clinton came in 2009 to free a couple of jailed journalists.

Jimmy Carter made the trip in 2010 to secure the release of Aijalon Gomes, who had been sentenced to eight years of hard labor for illegally crossing into the country to do missionary work.

In 2011, the State Department's envoy for North Korean human rights managed to successfully intervene in the case of Korean-American businessman Eddie Yong Su Jun.

Matthew Miller, a U.S. citizen, stands during his trial at the Supreme Court in Pyongyang, North Korea, on Sunday

His fate: A forced labor camp in North Korea - where Matthew Miller will be sent to and spend the next six years

Matthew Miller, a U.S. citizen, is handcuffed after his trial at the Supreme Court in Pyongyang, North Korea, Sunday, Sept. 14, 2014

A North Korean flag flies at the Supreme Court where a trial of Matthew Miller, a U.S. citizen, was to be held, in Pyongyang, North Korea, Sunday, Sept. 14, 2014. North Korea's Supreme Court on Sunday sentenced Miller to six years of hard labor for entering the country illegally and trying to commit espionage

The United States has no diplomatic relations with North Korea and strongly warns American citizens against traveling to the country.

Uri Tours, a New Jersey-based travel agency specializing in North Korea tourism that handled the arrangements for Miller, said in an email Sunday that it was working to have Miller returned to his parents in the United States.

'Although we ask a series of tailored questions on our application form designed to get to know a traveler and his/her interests, it's not always possible for us to foresee how a tourist may behave during a DPRK tour,' the travel agency said in a statement on Friday, referring to North Korea's official name, the Democratic People's Republic of Korea.

'Unfortunately, there was nothing specific in Mr. Miller's tour application that would have helped us anticipate this unfortunate outcome.'