Chief Superintendent Steve Neill says officers would like to hear from people who may have seen anything unusual in Stanley Street at any time in the last few days.
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Cold with clear spells and scattered wintry showers. Localised snow accumulations and icy stretches may linger until Monday lunchtime
Margaret Mary MacDermott was last seen at her home in Fenhan in Newcastle on the evening of Friday February 12.
The win rekindle's the Black Cats' survival hopes and pile the pressure on United manager Louis van Gaal.