Allegations revealed by The Guardian and Channel 4 Dispatches that undercover police targeted the family of murdered black student Stephen Lawrence will be probed by two official investigations.
Home Secretary Theresa May told MPs the allegations would be considered by the inquiry into the undercover operations of the Special Demonstration Squad in London in the 1980s and 1990s, being led by Derbyshire chief constable Mick Creedon under the oversight of the Independent Police Complaints Commission.
They will also be scrutinised by the review of alleged police corruption in the original Lawrence inquiry, which is being conducted by Mark Ellison QC.
Prime Minister David Cameron described the allegations as "horrific" and vowed to "get the full truth out".
The Guardian published fresh claims today that Met officers infiltrated political groups protesting about police corruption.
One operative in the 1990s was said to have penetrated the Colin Roach Centre, named after a 21-year-old black Briton who died in the foyer of Stoke Newington police station.
A joint investigation into undercover policing by the Guardian and Channel 4's Dispatches programme has focused for former officer Peter Francis who said he was told to dig up "dirt" on Neville and Doreen Lawrence shortly after 18-year-old architecture student Stephen was killed in an unprovoked racist attack at a bus stop in south-east London in April 1993.
Francis said he was also asked to target Stephen's friend Duwayne Brooks, who witnessed the murder, and other campaigners angry at the failure to bring his killers to justice.
Stephen Lawrence's father Neville demanded a judge-led inquiry into suggestions of a smear campaign, dismissing as "completely unsatisfactory" Home Secretary Theresa May's announcement that they would be examined by two ongoing inquiries.
Former director of public prosecutions Lord Macdonald of River Glaven backed calls for judicial inquiry.
"It would be an absolute disaster if public confidence in undercover policing were to collapse as a result of this," he told BBC Radio 4's PM.
"We are going to continue to have drip, drip, drip revelations about what was going on. Let's just lance the boil and let's do it in a single inquiry."
Lawrence family lawyer Michael Mansfield told BBC Radio 4's Today programme: "There is a high likelihood that a lot of what he (Francis) has said is right given that this unit, or squad, has been in existence for over 40 years.
"My big question is: Who knew within the police , who authorised this public money being spent on this?"
"A squad of this size, involving these numbers, involving public expenditure of this kind does not go without authorisation from a very high level because if anything goes wrong they have got to be able to rely on the fact that they have got tacit, implicit support at the highest level," he added.
"I think that's why the public need to have something like the Leveson inquiry in relation to the ethics of policing in a so-called democracy."
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