Emergency officials in Oklahoma are assessing the damage after a violent burst of thunderstorms and tornadoes swept across the Midwest overnight, killing at least nine people and injuring dozens more.
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Police are not linking the explosion of the "incendiary device" to others which have caused panic in the city.
An estimated 70,000 claimants transferred to Employment and Support Allowance (ESA) from other benefits since 2011 were underpaid.
Plastics is one of a number of environmental issues facing the world's seas, along with rising sea levels and warming oceans.