US Capitol Police say they have re-opened the Hart Senate building, following an evacuation.
Tests on a suspicious package were negative, Reuters reports.
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Plumbers and heating engineers should be trained to help people living in homes that are too cold, according to new health guidelines.
Rain for the northwest, dry and cold elsewhere
Rejecting a showdown with Ed Miliband, David Cameron's terms sent to broadcasters reveal his deep dissatisfaction with the debate proposals.