North Korea has fired two more short-range ballistic missiles, this time from an inland site.
South Korean Joint Chiefs of Staff (JCS) spokesperson Um Hyo-sik was quoted by the Yonhap News Agency as saying that the missiles are presumed to be Scuds and were launched into the East Sea from an air base in the North's western province of Hwanghae.
The missiles flew 500km and landed in international waters, Hyo-sik said, noting that the country failed to impose a no-fly, no-sail zone.
"The North appears to be issuing a threat that it can fire missiles anywhere and at any time," Hyo-sik said.
South Korea's military has stepped up vigilance against additional launches and is in a state of full readiness, the JCS added.
The latest launch represents the first time Pyongyang has fired a missile from an inland area in nearly two decades, and is the 13th launch this year.
North Korea tested its 'newly developed tactical guided missile' on 26 June in the presence of its leader Kim Jong Un, and followed it with two short-range ballistic missiles, presumed to be Scuds with a range of approximately 500km, on 29 June, in violation of UN sanctions.