An interim report by MPs has described the practice of undercover police "borrowing" the identities of dead children "ghoulish and disrespectful".
It found that fake identity records such as passports, driving licences and national insurance numbers had been issued using the details of the dead children.
Today's report calls for the families of the children involved to be given an "unambiguous apology" from the forces involved.
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The Labour leader will also announce an inquiry into anti-semitism and other forms of racism to be chaired by Shami Chakrabarti.