More than a million South Koreans have visited the Mount Kumgang resort
A South Korean woman has been shot dead by a North Korean soldier in a special tourism zone in the mountains of North Korean, officials from the North say.
The 53-year-old is said to have strayed into a restricted area in the Mount Kumgang resort on the east coast.
A South Korean official said trips would be suspended pending an inquiry.
The resort has attracted more than one million South Korean visitors since 1998, and correspondents say this is the first incident of its kind.
The tours are managed by South Korea's Hyundai group.
According to North Korean officials, the woman had strayed into a restricted area in the early hours of Friday morning, failed to heed a warning, and was shot dead.
Her body has been returned to South Korea, where it is undergoing forensic examination.
South Korea's Unification Minister, Kim Ho-nyeon, who handles cross-border relations, said the woman had been shot after entering a fenced-off military area.
He said a major investigation was under way.
The Mount Kumgang resort offers South Koreans hotels, stores, a golf course and a spa - but it is also situated in a strategic naval zone.
The BBC's John Sudworth in Seoul says access to the special tourism zone is tightly controlled, and its border heavily policed.
Our correspondent says the resort - one of two North Korean tourist programmes - is one of the most visible symbols of the efforts by the two Koreas to engage in closer economic co-operation over the past decade.
The ventures have earned North Korea hundreds of millions of dollars in badly needed foreign currency.
The killing has overshadowed an earlier announcement by the South Korean President, Lee Myung-bak, that he wanted to re-open the stalled dialogue with North Korea.
In a shift from his previously tough stance, Mr Lee also offered to resume food aid to the North.