LONDON - Royal officials are urging media organizations not to publish unauthorized images of Prince George and Princess Charlotte, arguing that paparazzi are using increasingly dangerous tactics to snap images.

Kensington Palace, the official home of Prince William and his wife Kate, on Friday published a letter sent to media standards organizations, detailing recent incursions on the family's privacy. The palace says photographers have hidden in car trunks, obscured themselves in sand dunes and used other children to draw Prince George into view on playgrounds.

The palace says it presents a risk "in a heightened security environment."

"The worry is that it will not always be possible to quickly distinguish between someone taking photos and someone intending to do more immediate harm," the palace said.