Disabled adults and families with disabled children are challenging the legality of the Government's so-called "bedroom tax", arguing that it unlawfully discriminates against them.
Lawyers in 10 cases at London's High Court are seeking a ruling that the regulations, introduced on 1st April, "unjustifiably discriminate against housing benefit claimants who are disabled or care for disabled family members".
Outside court protesters gathered in support of the families.
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The PM raised objections to the Hinkley Point nuclear power plant deal during the coalition government, an ex cabinet member claims.
The Cursed Child opens in London on Saturday and will immediately be followed by the midnight release of the play's script book.
A dry and fine weekend for most, with scattered showers and heavier downpours in Scotland.