Police chiefs have been put under pressure to complete their probe into why senior officers failed to anticipate violent clashes during a student demonstration.
Metropolitan Police Commissioner Sir Paul Stephenson has appointed Commander Simon Pountain to oversee a "very quick internal review", which may be finalised on Friday.
More than 40 officers were injured and 50 people arrested as a hard core of protesters intent on violence occupied 30 Millbank in central London, smashing windows, lighting fires and throwing missiles, including a fire extinguisher, from a roof.
Senior officers are focusing on what intelligence was gathered before Wednesday's protest and what resources were put in place.
Policing minister Nick Herbert said yesterday the police response "clearly did not go to plan", but laid the blame for the "appalling scenes" lay "squarely and solely" with those who carried out the violence.
He also urged MPs to await the outcome of the review "rather than speculate on the intelligence failure", saying the inquiry would include "an examination of why numbers and violence on this scale were not anticipated".
The force planned to deploy just 225 officers to the protests, but had to double the numbers sent to the scene as the situation developed.
Prime Minister David Cameron called for "the full force of the law" to be used against those responsible and welcomed an inquiry by Sir Paul.
Sir Paul admitted his force underestimated the number of people who would join the march and mistakenly categorised the event as a low risk to the capital. Branding the violence an "embarrassment to London and to us", he pledged to examine what went wrong and apologised to those left inside 30 Millbank, who included senior politicians, for their "traumatic experience".
Peter Smyth, chairman of the Metropolitan Police Federation, said the man who threw the extinguisher ought to be charged with attempted murder.
The campaigns and communications officer for Goldsmiths University student union said the majority of students who made their way into the building did so peacefully, and claimed police were wrong to arrest them.
The violence was sparked as a peaceful march involving around 50,000 students and lecturers protesting against a proposed fee hike and university funding cuts passed the landmark building on the River Thames.
National Union of Students president Aaron Porter said: "I think we have to accept that we have lost a lot of public sympathy and actually that does undermine our case."
London mayor Boris Johnson said he hoped the small minority who were responsible "pay a serious price for their actions".
Students and staff were protesting against government plans to charge students up to £9,000 a year from 2012 - triple the current £3,290 fee.
