Emergency services training event
![The rescue helicopter touches down at Prehen...](https://www.northernirelandworld.com/webimg/legacy_oak_57950481.jpg?crop=3:2,smart&width=640&quality=65&enable=upscale)
![The rescue helicopter touches down at Prehen...](/img/placeholder.png)
Fears were raised on Friday that another tragedy had occurred along the Foyle River, as a search and recovery helicopter was seen, apparently combing the river to the south of the city.
Thankfully, it turned out to be a joint training exercise, as the attached video shows...