NEW : China says they often use email addresses from other countries . North Korea has staged similar attacks in the past , experts says . The outages come amid heightened tensions on the Korean Peninsula , with the North angrily responding to a recent U.N. Security Council vote to impose tougher sanctions on Pyongyang after the country 's latest nuclear test last month . Previous attacks linked to the North have been traced to Chinese addresses . Overall , broadcasters targeted ; social networks unaffected , expert reports .
NEW : China says they often use email addresses from other countries . North Korea has staged similar attacks in the past , experts says . Previous attacks linked to the North have been traced to Chinese addresses . Overall , broadcasters targeted ; social networks unaffected , expert reports .