Updated

The adopted son of Pink Floyd guitarist Dave Gilmour was jailed for 16 months Friday on charges of violent disorder during student fees protests in London last December.

Charlie Gilmour, a 21-year-old student at Cambridge University, was involved in an attack on a convoy carrying the Prince of Wales and his wife, Camilla, after the royal couple became inadvertently mixed up in the protest on their way to a theater performance.

Gilmour, who admitted drinking and taking LSD and Valium before the protest, sat on the hood of one of the cars in the convoy that carried royal protection officers. He threw a trash can, which missed the royal car, but hit another vehicle in the convoy.

Earlier, he was seen shouting at police in central London's Parliament Square, while waving a bag of food.

The court was told he had shouted, "Let them eat cake, they said, but we won't eat cake. We'll eat fire and ice and destruction because we're angry, very f*ck*ng angry.

We refuse to do anything we're told. They broke the moral law. We're going to break all the laws."

Some 30,000 students laid siege to the square before the Government's vote on tuition fees on Dec. 10. One student urinated on the Winston Churchill statue in the square and Gilmour was pictured swinging from a war memorial. He later expressed his "deepest apologies for the terrible insult to the thousands of people who died bravely for our country."

The judge at Kingston Crown Court in southwestern London called Gilmour's behavior "deeply offensive" and said he caused public outrage. "What you did went far, far beyond proper protest," he added.

Gilmour's biological father is the poet and playwright Heathcote Williams but he was adopted by the Pink Floyd rock star when his mother, writer and journalist Polly Samson, remarried.

David Gilmour was among family and friends who watched proceedings from the public gallery.