Labour's shadow justice secretary Sadiq Khan has suggested that the coalition should bar G4S and Serco from bidding for future government contracts, including a tender to run the probation service.
He also called for both the police and Serious Fraud Office to investigate all of the contracts that both companies currently hold with government departments.
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His representatives said Cassidy, who was hospitalised last week, died "surrounded by those he loved."
The company’s recently appointed Chief Executive Dara Khosrowshahi said the breach was made by two individuals outside the company.
The Chancellor will conjure up more homes; better roads (complete with driverless cars); improved trains and extra funding for the NHS.