(ATTN: UPDATES throughout with background)
SEOUL, March 3 (Yonhap) -- North Korea fired six short-range projectiles into the East Sea on Thursday, apparently in anger over the United Nations' adoption of its harshest-ever resolution punishing Pyongyang for its recent nuclear and long-range rocket tests, officials said.
The projectiles were fired from Wonsan, a port city along the east coast, at around 10:00 a.m. They fell into the East Sea, according to Defense Ministry spokesman Moon Sang-gyun and military officials.
The ministry is investigating the launch of the projectiles to uncover more details, including the type of projectiles used, the officials said.
Sources say the projectiles could be 300 millimeter rockets or short range missiles. They said the projectiles flew 100 to 150 kilometers before falling into the sea.
It was North Korea's first launch of short-range weapons into the sea so far this year. In the previous launch, North Korea fired off three KN-01 anti-ship cruise missiles into the East Sea, also from Wonsan.
The move came just hours after the U.N. Security Council adopted the harshest-ever sanctions on North Korea in New York.
The sanctions, Resolution 2270, require new, mandatory inspections of all cargo going into and out of the North and bans North Korea's exports of coal, iron and other mineral resources, a key source of hard currency that accounts for nearly half of the country's total exports.
The latest show of force was conducted without the necessary process of declaring a no-sail zone in advance, another military source said, highlighting the defiant nature of the firing.
Down the road, North Korea is likely to increase and diversify such military actions, particularly ahead of South Korea's large-scale joint military exercises with the United States slated to kick off on Monday, experts said.
The looming implementation of the new U.N. resolution will squeeze Pyongyang's finances and the livelihood of North Koreans, further enticing the North Korean regime into fomenting an external crisis in order to quell internal complaints, they said.
"The short-range projectile launch could be followed by additional provocations," a military official said, adding that the military is on the alert for all possibilities.
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