The gunman at Arapahoe High School in Colorado was looking for a specific teacher when he was confronted by a student, local media has reported.
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The win sends the Scot through to the last eight where he will face either Japan's Kei Nishikori or France's Richard Gasquet.
People "would not want" international footballer Jerome Boateng as their neighbour, according to a German politician.
The paralympian posted a time of two minutes and 57 seconds on Sunday.