(ABC NEWS) -- The South Korean military is on high alert preparing for North Korea's possible mid-range missile test "anytime soon," while Pyongyang seeks to grab international attention and build an image at home of Kim Jong Un as a formidable leader.
"In the past, North Korea has launched missiles in early morning hours seeking 'a surprise effect.' So both South Korea and the U.S. forces are operating intelligence assets 24 hours," South Korean Defense Ministry spokesman Kim Min-Seok said.
Pyongyang is expected to launch its untested Musudan missile with a range of 1,800 to 2,180 miles from its eastern coast. It could reach as far as the Japanese island of Okinawa, and Guam, where U.S. military forces are located. The missiles could obviously also threaten mainland Japan.
North Korea has launched various kinds of missiles in the past but with advanced notice to clear waters before the test. It has yet to notify neighboring nations but experts believe the launch could come any time in light of recent tensions.
Pyongyang has escalated its threatening rhetoric in the past few weeks in protest of the latest U.N. sanctions and the annual U.S.-South Korean military drills. It has vowed to launch a nuclear attack on the United States and South Korea.
The last remaining ties and symbol of inter-Korean cooperation, the Gaesong Industrial Complex, was shut down this week. The North warned foreigners in both North and South Korea to evacuate by today.
Such threats have come almost on a daily basis while Pyongyang prepares to celebrate the 101st birthday of Kim Jong Un's grandfather and founder of North Korea, Kim Il Sung April 15. That day is one of the most important festivities to North Koreans with additional rations, clothing and candy treats for the children.
The movement of Musudan-type missiles being prepared for a test-launch has been closely monitored by U.S. and South Korean surveillance. Two Musudans were spotted transporting to the eastern coast last week and disappeared from the radar for a while.
They have now been spotted, fueled and ready to be launched in Wonsan, Gangwon Province, just above the North-South border on the east coast of North Korea.
In South Hamgyong Province, north of Wonsan, four or five mobile Transporter Erector Launchers (TEL) showed up recently, hinting North Korea might launch short-range scud missiles and Rodong missiles in addition to the Musudan.
North Korea in the past has launched multiple number of different kinds of missiles when testing a newer model; for example, in 2006 July and 2009 July, they shot seven missiles each.
"They want to show off military power and maximize tensions by doing this," Park Chang-Kwoun, researcher at the Korea Institute for Defense Analyses, said. "Besides, this is a clever way of confusing the U.S and South Korean intelligence."
In North Hamgyong Province bordering Russia, several missiles were also spotted, according to Japanese Asahi Newspaper. The province is where North Korea has built a full-scale launch pad from which they unsuccessfully test-fired its long-range Daeopodong 2 missile three times in 2006, 2009 and 2012.
The big question is in which direction North Korea will fire these missiles. The Japanese government fears it might fly near, over and on its territory, and the South Koreans are worried about the possibility of firing southward.
In Japan, the national J-Alert emergency warning system has been activated, in case of any missile launch. Officials called on cities to inspect receivers to make sure they were functioning, in case they needed to be notified of any falling debris.
The defense minister inspected PAC-3 missiles deployed throughout the country today on camera and two Aegis destroyers equipped with missile interceptors have been sent to nearby seas.
The U.S. Navy also currently has three Aegis destroyers patrolling in waters near Japan and around Guam.
In Seoul, the public has been calm about the threats from North Korea, but signs of concern are slowly on the rise. Some parents kept children from going to school, and social media is filled with questions of worry.
"I don't think Kim Jong Un is crazy enough to start a war, but this is too stressful," said Lee Joo-Mi, a fashion consultant, while having an Italian lunch with several friends in Gangnam.
Her friend, a professional model and lecturer, agreed.
"It was fine until my friends abroad kept emailing me to stay safe and they were praying for me," said On Mi-Jung said. "I just ordered a wartime emergency backpack on the Internet, just in case."
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