The US military said that the latest launches involved two Scud missiles and one Rodong, Reuters reported.
Two of the missiles were presumed to be short-range Scuds and flew between 500 to 600 kilometers (311 to 373 miles) before falling into the East Sea, according to the JCS. The trajectory of the third missile is still under investigation.
He added that the decision to deploy the Terminal High Altitude Area Defense (THAAD) can be seen as part of the existing arrangement, and thus does not call for parliamentary approval.
The UN Security Council has slapped a series of sanctions against the hermit state that ban North Korea from conducting ballistic missile tests.
"We strongly condemn this and North Korea's other recent missile tests, which violate U.N. Security Council Resolutions explicitly prohibiting North Korea's launches using ballistic missile technology", said Commander Gary Ross, spokesman for the Pentagon.
A South Korean Joint Chiefs of Staff official said: "Our assessment is that it was done as a show of force". The launch was also described as an "armed protest" by Pyongyang, according to Yonhap.
Both South Korean and United States troops stationed in the South also have Patriot anti-air defense systems that can intercept enemy missiles at low altitudes.
Seongju residents have complained that they weren't consulted about the THAAD plan, and raised concerns about the impact the system could have on their health, the environment, and the local economy.
South Korea's Prime Minister Hwang Kyo-ahn said Tuesday that missile tests had been "a rare phenomenon in the past", but have been occuring "continuously" this year. "This measure is supposedly to counter North Korean ballistic missiles and provide additional security, yet this is a controversial move that [is] likely to escalate tension in the region, by provoking North Korea, China and Russian Federation into a spiraling arms race", says the petition, which was reportedly launched by Koreans in the US. Many experts in Seoul say it's highly likely the North will continue its protest against the THAAD deployment, so we'll have to keep a close eye on how this plays out. The Nodong missile is said to have a range of over 1,300 kilometers, putting most of Japan within range.
This article was written by Kim Tong-Hyung from The Associated Press and was legally licensed through the NewsCred publisher network.