North Korea has fired two short-range ballistic missiles into the ocean off its east coast, the fourth such test in under two weeks.
South Korean defense officials say the suspected Scud missiles fired Wednesday from the western Hwanghae province had a range of about 500 kilometers.
The missiles landed in the body of water South Korea refers to as the East Sea, and which Tokyo calls the Sea of Japan. Yoshihide Suga, the Japanese chief cabinet secretary, condemned the launch.
"The missile launch is a violation of the U.N. sanctions up to today, and we strongly protest against North Korea for launching the ballistic missiles again, despite our opposition," said Suga.
In recent weeks, North Korea has expanded its U.N. sanction-defying ballistic missile tests while pushing South Korea to accept a deal to reduce tensions.
Seoul has rejected the offer, saying Pyongyang must first take steps to show it is committed to dismantling its nuclear program.
Meanwhile, North Korean state media have announced the death of one of the chief architects of Pyongyang's nuclear and missile programs.
The Korean Central News Agency (KCNA) says retired General Jon Pyong Ho died Wednesday of natural causes at the age of 88.
Jon, who retired from public life in 2011, played an instrumental part in North Korea's first two nuclear tests in 2006 and 2009.
He also helped secure a deal in the 1990s with Pakistan, which offered uranium enrichment knowledge in exchange for the North's missile technology.
KCNA says Jon, who was the target of international sanctions, will receive a state funeral led by North Korean leader Kim Jong Un.
The news agency praised Jon for helping turn North Korea into a "powerful elite revolutionary army" and a "nuclear weapons state."