Michigan Senator Carl Levin says his regional office has received a suspicious letter, reports Associated Press.
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Sydney siege victim Katrina Dawson was killed by police bullet fragments, an inquest has heard.
Experts say a trial into an early Ebola vaccine shows it is safe, but did not perform as well as had been hoped.
Frequent snowfall expected across much of the north this evening and strong northeasterly winds will make it feel noticeably cooler.