Smile of freedom: Knox flies home via Heathrow

Amanda Knox today flew through London with VIP security as she returned to America a free woman after being cleared of the murder of British student Meredith Kercher.

She was given treatment normally reserved for members of the Royal family, foreign dignitaries and film stars at Heathrow Airport. The 24-year-old and her family flew from Rome to London en route to her native Seattle, where she is due to be met with multi-million-dollar book and movie offers to tell her story.

As she left the country where she has spent four years in jail she said she has "no bitterness".

Her lawyer Carlo Dalla Vedova said: "She was calm, serene and looking forward to going home and just spending some time with her friends and family. She wants to get on with her life. She is a clever and intelligent girl who has been through a lot - one day in prison is bad enough but four years is even worse."

The 24-year-old was sensationally cleared of the murder and released from her 26-year sentence last night, alongside ex-boyfriend Raffaele Sollecito, in a historic decision in Perugia where Meredith was killed.

She was set to be met at Heathrow and escorted to the Windsor Suite - normally reserved for royalty and celebrities at a cost of about £2,000 - in order to bypass the terminal building. Her BA flight was due to land at 1.30pm, with the onward flight leaving at 3.15pm.

In Italy Knox was taken to the airport police station to sign various forms - even anxiously calling Mr Dalla Vedova to check everything was in place for her to go through immigration.

Knox was said by onlookers to be "looking tired and drawn" as she tried to avoid journalists who had been waiting for her at the airport since dawn.

Dressed in black leggings, grey cardigan and a dark top, Knox was pulling a large black suitcase as she left the airport police office to join her parents. The family had been driven to Rome from Perugia late last night in two black Mercedes - one a people carrier which had been provided by the Italo-American Foundation, whose president MP Rocco Girlanda had written a book about Knox in prison and campaigned for her innocence.

Spokesman for the Foundation Corrado Maria Daclon said: "Amanda is really very exhausted after spending four years in prison. We hugged each other warmly as she was let out. She also asked me to thank the Italian public who have supported her publicly throughout her ordeal.

"She said she could not have coped with being unjustly jailed for four years if it had not been for their support - they gave her strength and believed in her innocence. Now someone needs to shoulder the responsibility for what happened. This has been one of the most serious errors of justice that we have had in our country and we have had many."

Mr Dalla Vedova said: "This case should never have come to court. Will there be an investigation? I doubt it. Amanda will now have some time in Seattle and then get on with her life and her family will also want to get back to theirs."

Mr Daclon added: "She is certainly very drained but even after all this time she does not have any resentment or animosity."