Queen Elizabeth II: Water patrols introduced ahead of committal in Windsor
Police will patrol "exceptionally busy" waterways ahead of the Queen's committal service on Monday, which follows her state funeral in London.
Thames Valley Police said specialist officers and the Environment Agency would search the water and river banks around Windsor as more people arrive.
The force added it would work with British Transport Police to monitor Windsor and Eton Riverside station.
Yesterday, patrols by mounted officers and a drone unit were also introduced.
Thames Valley Police has also warned visitors that parking around Windsor is £12, with card payment accepted only on arrival.
But it said information about parking for Monday would be released "in due course".
Her Majesty's state funeral will take place on Monday in Westminster Abbey, attended by her family, senior UK politicians and heads of state from across the world, as well as representatives from the charities she supported.
Following the funeral, the coffin will travel in procession from the abbey to Wellington Arch and from there it will travel to Windsor.
The state hearse will then take the coffin along the Long Walk to St George's Chapel at Windsor Castle, for the committal service.
Follow BBC South on Facebook, Twitter, or Instagram. Send your story ideas to [email protected].