A woman has been arrested over the leak of findings about the fatal police shooting of Brazilian Jean Charles de Menezes on the Tube, it has emerged.
Mr Menezes was shot a day after the failed London bombings
The 43-year-old was arrested at one of a number of London addresses searched.
The Independent Police Complaints Commission (IPCC) leak prompted claims police had covered up details of the shooting at Stockwell station in July.
No details were given on the grounds for Wednesday's arrest. The woman was later released on police bail.
Electrician Mr Menezes was shot by police on 22 July - the day after several failed bomb attempts - when he was mistaken for one of the bombing suspects.
The leak is being investigated by Leicestershire Police after ITV News ran details of the IPCC inquiry into the shooting.
A police statement said: "On Wednesday 21 September, Leicestershire Constabulary, supported by officers from the City of London Police, executed a number of search warrants at addresses in the London area.
The Menezes family demanded the resignation of Sir Ian Blair
"A 43-year-old woman was arrested at one of the London addresses and later released on bail pending further inquiries."
The leaked information contradicted much of what had previously been thought about Mr Menezes' death and led his family to demand the resignation of Metropolitan Police chief Sir Ian Blair.
Scotland Yard was quoted as saying that Mr Menezes' "clothing and demeanour" added to suspicions that he was a suspected suicide bomber.
However, the leaked documents and photographs show the body of Mr Menezes, on the Tube where he was shot dead by police, wearing a denim jacket - not a bulky one as previously described.
At the end of August, the IPCC announced an inquiry into how the documents were leaked, led by former Chief Inspector of Constabulary for Scotland Bill Taylor.