This was what I was alluding to yesterday. Turbine/fan blades breaking loose and getting sucked into an engine can be catastrophic.
Blades will break/detach for a number of reasons, including manufacturing, installation, and maintenance issues.
After a similar incident back in the 90s, we (USAF and the engine manufacturer) determined a certain production lot of blades had been improperly heat treated in their manufacturing process.
The blades are reasonably strong but if any one blade fails it will throw the turbine out of balance and tear itself apart. I understand that a duck or goose can just ruin a turbine. There have been several airports that have had problems with birds.