Scotland Yard denies suggestion poor police communication led car carrying Charles and Camilla into student protests

Police have denied that a breakdown in radio communication led to a car carrying Prince Charles becoming caught up in violent student protests in central London.

The Rolls-Royce carrying Charles and Camilla, Duchess of Cornwall was daubed with paint and had a window smashed by a gang shouting “Off with their heads!” on Thursday.

It has been claimed that royal protection officers were using a different radio frequency to riot police, which led to the car being sent into the protests, but Scotland Yard said both teams were in communication.

The incident has led to serious questions being raised about the Met police’s handling of the protest, which also saw a 20-year-old student undergo brain surgery after allegedly being hit with a truncheon.

Former home secretary Alan Johnson, told BBC Radio 4’s Today programme he was “amazed” by the suggestion that protection officers had not been fully in touch with colleagues policing the demonstration.

Johnson, now shadow chancellor, added: “I am amazed by that because I am a very small fish in these things compared to the heir to the throne and I would just like to know what went on there, because in my experience they are really meticulous about ensuring that the route ahead is well known and that they avoid these kinds of incidents.”

Scotland Yard has launched a major criminal probe into mass protests in London against the rise in tuition fees.

The investigation was announced after David Cameron demanded that demonstrators face the “full force of the law”.

The prime minister said it was not possible to blame the disorder on a small militant element when so many in the crowd on were acting in an “absolutely feral way”.

“The scenes people saw on their TV screens were completely unacceptable,” he said. “I don’t think we can go on saying a small minority were there. There were quite a lot of people who were hell bent on violence and destroying property.

“It is not acceptable, it is against the law to smash property, to behave in that way, to attack police officers, and I want to make sure that they feel the full force of the law.”

Police have so far arrested 33 people following the chaotic scenes in central London that left dozens of protesters and several officers injured.

The public order investigation will cover all the fee protests held between 10 November, when students broke into Conservative party headquarters in Millbank, and Thursday’s demonstration in Parliament Square.

The Metropolitan police commissioner, Sir Paul Stephenson, said an investigation was being held into the security breach and added that armed protection officers showed “real restraint” not to open fire as the situation slipped out of control.

“I do think that the officers who were protecting their royal highnesses showed very real restraint – some of those officers were armed.

“Their priority was to get that car to the point of safety, which was the venue, and that was achieved, but it was a hugely shocking incident and there will be a full criminal investigation into it.”

Meanwhile, the Independent Police Complaints Commission (IPCC) is examining the incident involving Alfie Meadows, a philosophy student at Middlesex University, who underwent a three-hour operation after he was struck on the head during the demonstrations on Thursday. He had been attempting to leave the protest outside Westminster Abbey, when he was hit with a police truncheon, according to his mother.

The son of Pink Floyd guitarist David Gilmour apologised yesterday for swinging from a union flag on the Cenotaph in Whitehall during the student protests on Thursday. Charlie Gilmour, 21, said he was “mortified” by his “moment of idiocy”, after he climbed on to the memorial to Britain’s war dead.

Gilmour, a history student at the University of Cambridge, said he was deeply ashamed. “I would like to express my deepest apologies for the terrible insult to the thousands of people who died bravely for our country that my actions represented,” he said in a statement. “I feel nothing but shame. My intention was not to attack or defile the Cenotaph. Running along with a crowd of people who had just been violently repelled by the police, I got caught up in the spirit of the moment.”

He apologised to other protesters, saying that his actions had detracted from the cause the protests were trying to highlight.

Aaron Porter, president of the National Union of Students, stressed that protests should be peaceful, but said young people were “engaging with the issues” over tuition fees.

“Peaceful protest is an integral part of our heritage and it is the responsibility of the police to help facilitate that,” he said.

“Throughout this campaign, thousands of young people who have been in the past dismissed as politically apathetic have engaged with the issues and are seeking a way to express their opinions.”

Education news, comment and analysis | guardian.co.uk