Gregg Zoroya

USA TODAY

Travel warnings for American tourists keen on North Korea have always been dire with admonitions from the U.S. State Department about the risk of arrest, long-term detention, coerced public statements and public trials.

This week a new alert was added — something sounding an awful lot like becoming a prisoner of war: "North Korea's system of law enforcement ... threaten(s) U.S. citizen detainees with being treated in accordance with 'wartime law,' " a revised State Department travel warning said.

The updated language follows the latest heightening of tensions between the U.S. and North Korea in July when the Obama administration for the first time imposed personal sanctions against North Korean Leader Kim Jong Un for human rights abuses.

North Korea responded by calling the move an "act of war" and severed one of the last remaining communication channels between the two nations through North Korea's United Nations mission in New York.

North Korea: U.S. declared war with sanctions

North Korea also said it would begin detaining Americans "under the wartime law of the DPRK," the acronym for the Democratic People's Republic of Korea. The revised travel warning from the State Department was the consequence.

"This update adds information related to North Korea’s published threats about how it will treat U.S. citizens in the DPRK," Kevin Brosnahan, spokesman for the Bureau of Consular Affairs at the State Department, said Friday.

Andrea Lee, CEO and founder of one of the few U.S.-based travel companies operating in North Korea, said the fierce warnings have proven to be a "double-edged sword" for tourism.

"On the one hand, yes, it's not positive. But on the other hand, it makes people curious and they want to go and see it for themselves," Lee said.

In addition to sites in the capital of Pyongyang, the country features scenic mountains and even surfing and skiing opportunities. There is also a sense of excitement about traveling to a country few outsiders have seen, Lee said.

"I really think it's sort of this sense of adventure. People are tired of going to the same old places. People want to see the world and they want to go to places no one else has been to before," Lee said.

She said her New Jersey-based Uri Tours takes about 500 Americans into North Korea each year and has had only lost one tourist detained in the communist country. Matthew Miller was taken into custody when he arrived with a Uri tour group in 2014, tore up his visa and said he was seeking asylum. He was released eight months later.

Lee maintains that travel into North Korea is safe. "But you do need to follow the rules," she said.

The State Department said at least 14 Americans have been detained in North Korea in the past 10 years. Among the latest was Virginia student Otto Warmbier, who was sentenced to 15 years of hard labor after pealing a poster off a hotel wall during a visit to North Korea with a tour group in January. He was convicted of subversion. The Obama administration has demanded the 21-year-old student's release.

It's unclear how many Americans try to visit North Korea. Tourism is conducted almost exclusively through Beijing and tour groups. The London-based Telegraph reported earlier this year that 5,000 to 6,000 foreigners visit North Korea each year.

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The State Department warns Americans that any of a number of otherwise innocent acts can be treated as crimes in North Korea, including possessing material critical of the government, having "unauthorized" interaction with North Korean citizens, shopping at unauthorized stores or, as happened in Warmbier's case, "removing or tampering with political slogans and signs or pictures of political leaders."

U.S. puts N.K. leader Kim Jong Un on sanctions list for human rights abuses

Since there are no diplomatic ties between the U.S. and North Korea, there is little the American government can do if a traveler is arrested, the State Department warns.