More than 100 tiger sharks were filmed preying on a massive school of fish off the east coast of Noosa, Australia, according to the Australian Broadcasting Corporation (ABC) and other reports.
The event was captured on video by the Sunshine Coast Helicopter Rescue Service, which happened to be in the area, returning from a trip to Fraser Island.
(Tiger shark; Image: Albert Kok)
When you see the sharks, you'll understand why the crew on the helicopter immediately alerted local lifeguards.
"There were fishermen in the area," Rick Harvey, a spokesman for the helicopter service, told ABC.
He added, "There were no swimmers, but we have notified lifeguard command and they were letting their people know just to keep an eye out in case."
Here's one video report from ITN News:
And more footage of the sharks going in for the kill.