Bernalillo County sheriff's spokesman Aaron Williamson has said that the motive of the teenage boy who shot dead five people at a home in New Mexico is not yet known, the New York Post reports.
Mr Williamson also said that investigators were trying to determine any connection of the teenager to the victims and if the victims were related.
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New Army unit which will use psychology and social media to help Britain "fight in the information age" is being set up, the MoD announced.
Police proposals suggest that all frontline police officers should have the option of arming themselves with Tasers.
Snow showers and sleet expected to affect parts of Scotland and Northern Ireland, with snow extending further south.