Police are to publicly apologise for the use of names of dead children by undercover officers.
An investigation into undercover policing is under way by Metropolitan Police after it emerged that the practice of using the identities of dead children was widespread in the force.
None of the families of children whose names were used are thought likely to have been informed of this, said to be due to the risk of jeopardising the cover of officers, even though Scotland Yard has received speculative inquiries from relatives asking the force to say whether their dead child's identity was used.
Instead, a public apology is expected to be offered next week.
Operation Herne was set up in October 2011 to look at allegations made against the Met's special demonstration squad (SDS), including them using dead children's identities and engaging in inappropriate sexual relationships.
Derbyshire Police Chief Constable Mick Creedon, brought in to oversee the operation, recently said it was ''common practice'' for SDS undercover officers to use the identities of dead children.
Some 23 officers and 10 support staff have been deployed to Operation Herne. They have identified around 55,000 documents and have started to interview witnesses, including former SDS officers.
The investigation has already cost £1.25 million and is expected to cost another £1.66 million over the next year.
A Met Police spokesman said: "There is a thorough review and live investigation into allegations of inappropriate behaviour and practices involving historic undercover deployments. It would be inappropriate for us to provide a running commentary on specific allegations whilst this investigation is ongoing.
"The MPS must balance the genuine public interest in these matters with its duty to protect officers and former officers who have been deployed undercover, often in difficult and dangerous circumstances."