Officials of Toronto’s Hospital for Sick Children have been telling players to stop dropping lures on hospital grounds as it raises safety concerns.

Pokemon Go has been a huge worldwide success, with the augmented reality game launching in Canada last Sunday. In a statement, the hospital officials said:

“Unfortunately Pokemon Go can create many challenging issues and safety concerns for our patients and may impeded staff in their work. Our patients are some of the sickest in Ontario and may be going through a very difficult time in their lives. We ask that individuals respect their privacy and the hospital space.”

Officials are also worried some children could get upset as they may not be able to leave certain areas of the hospital to catch the digital creatures.

The augmented reality game, which overlays images of Pokemon characters over real life objects, has become a worldwide sensation in less than a week.

Pokemon Go is now available in the Canadian App Store as a free download. The game requires any device running iOS 8.0 or later and contains in-app purchases that range between $1.39 and $139.99.