A student's stabbed up to 20 teenage pupils at a high school near Pittsburgh, in the US state of Pennsylvania.
A spokesperson at a local hospital says some have suffered "significant injuries".
Police in Murrysville say they've arrested a boy:
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Multiple stabbings at US school
A student's stabbed up to 20 teenage pupils at a high school near Pittsburgh, in the US state of Pen...
TodayFM
2:35 PM - 9 Apr 2014
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