Enver Solomon, of the Children's Society, says the number of missing children from care means thousands of vulnerable children are finding themselves in great danger.
Watch Social Affairs Editor Penny Marshall's report on the ITV Evening News at 7.15pm on ITV1
Children's Minister Tim Loughton concedes the care system needs reform and says the Government needs to make sure the quality of data it is collecting on children in care going missing needs to be "high and consistent".
Detective Inspector Philip Shakesheff, of West Mercia Police, says he is "shocked and alarmed" by the lack of children in care who have been recorded as missing by the Department of Education.
He tells ITV News that in his force area last year 120 children in care were recorded as going missing for 24 hours or more. This figure conflicts with that released by the Department of Education, which showed 15 children in care went missing.
Official figures say that last year 930 children in care ran away and went missing for more than 24 hours, but ITV News has uncovered that, according to police figures, the real figure is closer to 5,000.
According to Department of Education figures, in 2011 there were 65,000 children in care in England and of those 930 went missing for 24 hours or more.
But figures seen by ITV News, based on police data, suggest that figure could be as many as 5,000.