Spending on private firms to provide 999 ambulances across swathes of Britain has doubled in three years, an investigation has found.
Senior medics and safety campaigners said they fear patient safety is being jeopardised by a heavy reliance on commercial firms to answer emergency calls.
An investigation by The Telegraph reveals that the amount spent by the NHS on private and voluntary services to provide 999 care has risen from £24m to £56m in three years.