According to Yonhap News Agency reports citing the JCS, the two projectiles were fired from the coastal city of Hamhung, which is roughly 30 miles north of where several previous missile tests have been fired.
Hamhung is home to a solid-fuel rocket engine production site. Solid fuel tends to be favored for rocketry weapons since it's always ready to fire and can be stored for long periods without fuel degradation, as compared to liquid rocket fuel.
The Republic of Korea Armed Forces are maintaining a readiness posture as military intelligence tracks the situation.
"We are aware of reports of a missile launch from North Korea, and we continue to monitor the situation," a senior US official told Reuters. "We are consulting closely with our Japanese and South Korean allies." They noted that at least one of the projectiles appeared to be similar to previous short-range missiles fired by the DPRK.
Saturday's test is only the latest in a series of short-range ballistic missile and guided rocket tests carried out by the socialist country in the last few weeks. Military observers have concluded the new weapons system being tested by Pyongyang is the KN-23, a mobile rocket platform unveiled last year. Pyongyang has described the weapon as a "newly-developed large-caliber multiple launch guided rocket system."
In a Wednesday statement following the previous missile test, North Korean leader Kim Jong Un said the exercise was intended as a warning to South Korea and the US to stop their simulated military drills, which Kim said violate the June 2018 agreement between him and US President Donald Trump to cease such exercises.
The North Korean tests do not violate that agreement, as US officials have verified, since they are short-range weapons and Kim only agreed to call off intermediate-range and long-range missile tests capable of carrying nuclear weapons and threatening the wider region.
Korea has been split into two countries since World War II, with the socialist-backed North and capitalist-backed South fighting a civil war that drew in world powers such as the US, Soviet Union, and China. The fighting ended in a ceasefire in 1953, but no permanent peace treaty was ever signed. Therefore, the peninsula remains split, separated by a demilitarized zone but characterized by an intense military competition.
The US has 28,000 troops stationed in South Korea, which Pyongyang has demanded be removed along with the cessation of military cooperation between Seoul and Washington and the signing of a permanent peace treaty; South Korea and the US have demanded Pyongyang destroy its nuclear weapons and ballistic missile programs, placing strangling economic sanctions on the country in an effort to force it to comply.
Reports emerged late last month that talks between the US and DPRK would resume soon, having been delayed since the February summit in Hanoi collapsed.