[cheekopekman]

there are many possibilities.
one thing for sure is earth quake causes rocks to be dislodged and fall at the gorge 

these rocks can hit and injure you. they can also fall and block your passage. 

further into the trail there aboriginal people.

the trial takes only 10-20 min to reach the end.

right now it's not clear what happened to them but it could be they are just somewhere in the forest or park. the cellphone reception is quite bad in that area.

I had been to Taroko Gorge or "Terror Gorge" before so I know lah!  It's a very narrow trail from 1 end of the mountain to the other end lah! Anyone can go missing very easily lah!