SEOUL - North Korea on Saturday test-fired three short-range missiles off its east coast, putting the South's military on alert ahead of a traditional harvest holiday.
The missiles, launched from a location near the southeastern port of Wonsan early Saturday, flew 210 kilometres (131 miles) before splashing down in the Sea of Japan (East Sea), the South Korean military joint chiefs of staff said.
They are believed to be new tactical missiles which the North has been testing in recent weeks.
"In light of their ranges and trajectories, the missiles fired today are of the same kind" as the missiles fired on August 14 and September 1, a military official was quoted as saying by Yonhap news agency.
"The launches are apparently aimed at developing new missiles with a longer range than that of the existing KN-02 missiles", which have a range of 170 kilometres, he said.
The South's military is keeping a close watch over the North ahead of the Chuseok holiday, which begins on Monday and ends on Wednesday, he added.
During the holiday, one of the South's most celebrated traditions, Koreans visit relatives and pay their respects to ancestors.
North Korea has fired a total of 111 missiles, all short- or middle-range, in 19 launches this year alone, Yonhap said.
The hardline communist state often fires missiles and rockets as a show of force or to express anger at perceived provocations such as joint US-South Korea military exercises, but the frequency of the recent tests is unusual.
UN resolutions bar North Korea from conducting any launches using ballistic missile technology.
But the North has defended the missile launches as a legitimate exercise in self-defence and a response to US war manoeuvres.