North Korea launched what seems to be short-range missiles into the East Sea on Saturday morning, according to South Korea's military.
The North fired several "unidentified projectiles" from the vicinity Gitdaeryong in Gangwon Province at around 6:49 a.m., said the Joint Chiefs of Staff (JCS).
Those flew more than 250 kilometers in the northeastern direction, it added.
South Korea and U.S. militaries are analyzing additional information. The allies are conducing their annual joint drills, called Ulchi Freedom Guardian (UFG), in Korea.
The North's provocation was immediately reported to President Moon Jae-in, added the JCS.
The presidential office Cheong Wa Dae convened a National Security Council meeting to discuss the issue.
It came a month after the communist nation test-fired another intercontinental ballistic missile.
On Tuesday, U.S. Secretary of State Rex Tillerson openly said in Washington that, "I am pleased to see that the regime in Pyongyang has certainly demonstrated some level of restraint that we've not seen in the past."
He expressed hope for dialogue with Pyongyang.
President Donald Trump also voiced cautious optimism, talking about the North's leader Kim Jong-un.
"I respect the fact that he is starting to respect us," Trump said at a campaign rally earlier this week. "And maybe - probably not, but maybe - something positive can come about." (Yonhap)
