London ( CNN ) -- Protesters made `` some contact '' with Prince Charles ' wife Camilla , Duchess of Cornwall , during a demonstration in London last week , Home Secretary Theresa May said Sunday . May , whose responsibilities include domestic security , refused to confirm Camilla was `` poked with a stick , '' as some British media have reported . Charles and Camilla 's car was hit with paint and a window was cracked as the vehicle drove through protesters en route to a show in central London on Thursday night . Neither of them was injured , although the duchess looked shaken as she got out of the car . May has not offered to resign over the incident , she said Sunday on Sky News . Police released images Sunday of 14 people they want to question in connection with violence at the demonstration , which was to protest government plans to let universities triple their tuition fees . `` We want the public to help us identify these people who may have been involved in violent disorder , attacking police officers and smashing buildings , shops and windows , '' Detective Chief Superintendent Matthew Horne said in a statement . `` The vast majority of the people we are seeking are suspected of committing serious offences of violent disorder and criminal damage , '' he said , without specifying whether any were directly involved in the attack on the royals ' car . Separately , police arrested a man Sunday for swinging on a flag at a London war memorial during the student protests . Charlie Gilmour , the son of Pink Floyd guitarist David Gilmour , apologized Saturday for doing that , but London 's Metropolitan Police declined to identify the man they arrested , other than to say he was 21 years old . Cambridge student Gilmour said : `` This is probably the worst thing I 've done '' on Facebook , his university 's student newspaper reported Saturday . `` I just wanted to swing from a flag , I did n't realise it was the Cenotaph . I feel so ashamed of myself right now . '' Gilmour and his mother did not immediately reply to CNN requests for comment . The man arrested Sunday is not one of the 14 people whose photo was released by police , they said . The Cenotaph , outside the Foreign Office in central London , commemorates Britain 's war dead , and is where Queen Elizabeth II and British officials lay flowers every November on Remembrance Sunday . A total of 34 people were arrested at the demonstration Thursday , the fourth in a series of protests against the planned tuition increase . British Prime Minister David Cameron said Friday that protesters who resorted to violence will `` feel the full force of the law , '' and blamed them for wreaking havoc in London during the pre-Christmas weeks . Addressing reporters , Cameron defended the government 's contentious move to triple tuiton at UK universities and said protesters , not the police , should be blamed for the chaos . `` I immediately rang the Prince of Wales , '' Prince Charles , said Cameron . `` We need to learn the lesson of this incident , '' he said . On Friday , police sifted through rubble strewn over London 's Parliament square , searching for clues and culprits in Thursday night 's protests , where students and their supporters , enraged by the tuition hike , broke windows and ambushed the royal vehicle . `` It is not the fault of the police , '' said Cameron . `` It was the fault of those who tried to smash that car . '' Members of the National Union of Students condemned any forms of violence , including from the police , they said in a statement on their website . `` Regarding many of the scenes that were witnessed yesterday , whilst it is clear that there were a small number of people involved who were inciting violence , many people were contained for a long period of time when attempting to take part in peaceful protest , '' the NUS stated . `` We are calling on the Metropolitan Police to have a full investigation into the clashes yesterday between protesters and the police and for it to look again at its tactics for policing demonstrations , '' it said . A photo of the royal couple , dressed in evening wear , made headlines as it showed the startled expressions on their faces as they sat in their Rolls-Royce before exiting for a Royal Variety Performance . The royal couple escaped unhurt . Police said the route had been cleared minutes before the royal couple was due to make their journey . The high-profile incident came late in a day of violent protests that left at least 12 officers and 43 demonstrators hurt . London 's Metropolitan Police issued a statement Friday condemning the protests and alleged vandalism that took place Thursday night , claiming protesters intimidated Christmas shoppers and bystanders . `` This has nothing to do with peaceful protest , '' the statement said . `` Students are involved in wanton vandalism including smashing windows in Oxford and Regent streets . '' The protests followed a vote in the House of Commons to approve a plan to raise the existing cap on tuition rates charged by universities from £3,000 to £9,000 a year . In U.S. dollars , that 's a nearly $ 10,000 a year increase -- from . roughly $ 4,700 to $ 14,000 . Lawmakers approved the plan in a 323-302 vote . The measure awaits approval by the House of Lords and a signature by the queen before it can become law .
NEW : 21-year-old arrested for swinging on a flag at war memorial . The heir to the British throne and his wife drove through protests Thursday . They were not hurt . Police release photos of 14 people they want to question over violence at the demonstration .