Margaret Hodge, who chairs the committee, has accused the DWP of making "poor decisions" at "considerable cost" to the taxpayer.
The report found that the department's decisions were overturned in nearly 40 per cent of appeals, and that Citizens' Advice had recorded a more than 80 per cent rise in the number of people asking for support on appeals in the last year alone.
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In her message Theresa May praised the "inspirational bravery" and "unbreakable spirit" of Mancunians in the wake of the blast.
ITV News has obtained exclusive footage of the moment armed police raided a house believed to be linked to the Manchester suicide bomber.
The Manchester Evening News set up a JustGiving page asking people to support the families of those affected by the suicide bombing.