An urgent review has been ordered after a confidential child protection report drawn up by staff at the council involved in the Baby P scandal was left on a train, a spokesman for the authority said today.
The 15-page Haringey Council file, which included details about a boy taken away from his mother over fears he could be abused, was found in a railway carriage in London.
A council spokesman said: "This is an isolated case but of course the council is extremely concerned that sensitive papers relating to child safety appear to have been left on public transport.
"It is the position of the council that such documents should be stored and used securely.
"We will urgently review our procedures and tighten them where necessary to make sure it doesn't happen again."
A council worker has been suspended while the review is carried out.
Staff at Haringey were criticised after Baby P, later identified as Peter Connolly, was killed despite being on the council's child protection register.
The toddler suffered 50 injuries despite receiving 60 visits from social workers, doctors and police over the final eight months of his life - causing a huge outcry over his care.
A series of reviews identified missed opportunities when officials could have saved the little boy's life if they had acted properly on the warning signs in front of them.
Inspectors identified a string of "serious concerns" about the area's child protection services, which they described as "inadequate".
In a 16-page report, they condemned everything from poor record-keeping to a failure to identify children at immediate risk of harm.