After fourth Austin explosion, police warn of sophisticated ‘serial bomber’

  1. After fourth Austin explosion, police warn of sophisticated ‘serial bomber’  Washington Post
  2. Austin police warn of ‘serial bomber’ after fourth explosion shows ‘higher level of sophistication’  Los Angeles Times
  3. 4th blast in Austin leads police to believe a ‘serial bomber’ is on the loose  CNN
  4. Austin explosions: ‘Serial bomber’ hunted after tripwire sets off 4th blast  NBCNews.com
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