Local news is reporting that a wing fell off prior to impact
While we should wait for a more authoritative source than local news, there is regrettable precedent for inflight wing separation on the C-130.
One of the more horrifying things I've seen on video was a Hawkins and Powers A-model fire tanker suffering a center wing box failure while maneuvering hard at low altitude to make a fire drop. Both wings departed the airframe almost instantaneously.
The Hercules is an amazingly tough and well engineered bird, but cycle time and corrosion can make it structurally unsafe, just as with any other aircraft.