Police in Britain have rejected suggestions that a communication breakdown led to the Prince of Wales and Duchess of Cornwall being caught in student protests.
It has been reported that police guarding the couple were using a different radio frequency to those policing the London demonstrations.
Scotland Yard insisted the two teams were in contact and may have used mobile phones or e-mail.
A car carrying the prince and the Duchess of Cornwall was daubed with paint and had a window smashed during tuition fee protests on Thursday.
The BBC reports they were being escorted by outriders and Royalty protection officers to a theatre in central London when their car was attacked.
Police said the route along Regent Street had been checked minutes before the incident and was deemed to be safe.
The incident took place during violent clashes on Thursday when MPs voted to allow university tuition fees to rise to up to £9,000 per year in England.
Prime Minister David Cameron has condemned the disturbances.
Scotland Yard said it is investigating student disorder between 10 November - 10 December.