(ATTN: UPDATES with more details
SEOUL, May 18 (Yonhap) -- North Korea on Saturday launched three short range guided missiles into the sea off the Korean Peninsula's east coast, South Korea's Ministry of Defense said.
The ministry said it detected two launches in the morning, followed by another in the afternoon. It said the missiles were fired in a northeasterly direction away from South Korean waters.
"A more detailed analysis will be needed but the missiles launched may be a modified anti-ship missile or the KN-02 surface-to-surface missile derived from the Soviet era SS-21 that has a range of about 120 kilometers," a Seoul official said.
He said judging by the trajectory and distance traveled, those missiles fired were not medium- or long-range ballistic missiles.
The communist country had deployed two Musudan intermediate-range missiles on its east coast along with medium-range Rodong missiles in April in an apparent countermeasure against joint South Korea-U.S. military exercises under way but they were later pulled back.
The Musudan is estimated to have a range of up to 4,000 kilometers that could reach the U.S. territory of Guam, while Nodong with a reach of 1,500 kilometers can cover all of South Korea and parts of Japan.
"All missiles launched fell into the sea," a South Korean Defense Ministry official said, requesting that he not be identified. He speculated that the launch is likely part of a military exercise or a missile test.
Defense Ministry officials said they have beefed up monitoring on North Korea and are maintaining a high-level of readiness to deal with any risky developments.
The launches come a little over two months after the North fired off two short-range missiles into the sea off its east coast.
The presidential office Cheong Wa Dae said it has been closely watching the North's move to test-launch the missiles.
"All information has been shared real time between the presidential office and the defense ministry," Cheong Wa Dae spokeswoman Kim Haing said.
She said South Korea does not consider the North's latest missile launches a serious threat to its security.
"The situation is being monitored carefully," she said.
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