The US State Department issued a new warning against traveling to North Korea on Thursday, citing the "serious risk of arrest and long-term detention."

"North Korea's system of law enforcement ... imposes unduly harsh sentences, including for actions that in the United States would not be considered crimes and which threaten US citizen detainees with being treated in accordance with "wartime law of the DPRK," the department said in the latest warning.

The department issues the anti-North Korea travel warning every three months.

"At least 14 US citizens have been detained in North Korea in the past ten years," the department said.

"Numerous foreigners have been held in North Korea for extended periods of time without being formally charged with any crimes.

Detained foreigners have been questioned daily for several weeks without the presence of counsel and have been compelled to make public statements and take part in public trials," it said.

Two American citizens -- college student Otto Warmbier and Korean-American pastor Kim Dong-chul -- are currently detained in the North after being sentenced to long prison terms for what Pyongyang calls subversive acts against the country.

American citizens have often been detained in North Korea on charges of anti-state and other unspecified crimes. Widespread views have been that Pyongyang has often used the detentions as bargaining chips in its negotiations with Washington. (Yonhap)