North Korea has sent a fax to South Korea threatening to attack "without notice" in response to anti-Pyongyang rallies held on the second anniversary of Kim Jong Il's death earlier this week, South Korea's largest news agency reported Friday.
According to Yonhap news agency, the north's powerful National Defense Commission sent the message to South Korea's National Security Council through on Thursday.
NBC News was unable to independently verify the report.
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The North Korean military apparently condemned the rallies by several conservative groups and defectors from the isolated communist state on Tuesday, saying they insulted North Korea's "highest dignity," referring to its young leader Kim Jong Un.
Meanwhile, top Pentagon officials warned on Thursday that the execution of his uncle last week is an example of the worrisome unpredictability of that regime and could be a prelude to some kind of provocation by Pyongyang.