The body of an 11-year-old boy has been recovered after he went into a river, police have said.Mackenzie Swift was last seen entering the River Don, near Mexborough, South Yorkshire, on Saturday evening.The alarm was raised when he did not emerge from the water, prompting a 48-hour search.On Tuesday, South Yorkshire Police said they had recovered a body.Chief Superintendent Pete Thorp, district commander for Doncaster, said: “First and foremost, on behalf of all who have been involved in the operation to find Mackenzie since Saturday, I send deepest sympathies to his family and friends.“Losing a child is every parent’s worst nightmare and I know the impact this news will have on the wider community and particularly Mackenzie’s school.“I would also like to thank the local community, who enabled us to conduct our search and recovery with very few onlookers and cameras to give Mackenzie and his family the dignity they deserve.“Not only for that, but also for the offers of assistance – we knew we had many members of the public willing to do anything they could to help.”