'Off With Their Heads!' Mob's Royal Attack of Opportunity

Dec. 10, 2010— -- It was pure chance that led an angry street mob in London to viciously attack a car carrying Prince Charles of Wales and his wife, a photographer in the midst of the mob said today.

"This was a breakaway group trying to get into the main protest in Parliament Square," Associated Press photographer Matt Dunham told "Good Morning America." "They couldn't get in because the police weren't letting them ... and they then basically went on a rampage through central London."

Dunham, who captured a memorable picture of Camilla in visible panic inside the car that is on the front page of newspapers around the world, said he had no idea the royal couple was in the area Thursday, "nor did the protestors."

When they did spot the royal car, however, the students -- who have been protesting school tuition hikes for weeks -- surged around it, hitting and kicking the car while at least one person yelled "Off with their heads!" The rowdy mob smashed windows in the Rolls Royce and splattered it with paintballs.

"I was filming, she [Camilla] was really terrified and Prince Charles was also terrified so he pulled her into protection and Camilla sat down on the floor," one witness, Adnan Nazir, said. "It was quite a chaotic scene, from people trying to damage the vehicle to photographers trying to take pictures. I'm not sure what was going on. It was surreal. ... You never expected the presence of the royal couple."

Click here for images of the London protests.

Both the royals, who were on their way to a charity concert, were unharmed in the attack. Leaving the concert later. Camilla did her best to laugh off the incident saying, "There's a first time for everything."

But the question on the minds of Britons this morning is how the incident could have happened at all, former press secretary for the Queen, Dicky Arbiter told "GMA."

Clarence House responded to the failure of the security team around the royal couple, saying the royals understand "the difficulties the police face and are always very grateful to the police for the job they do in often very challenging circumstances."

British Prime Minister David Cameron said the "full force of the law will be used on the mob."