Free images results:

Caution pictures, stock photos and images


Safety sign Stock Image
Author: Freds
Warning Stock Photo
Author: Marilyna
Barbs Stock Photography
Author: Gautier

Also, here are some commercial RF-licensed images that match your search criteria:  
Caution Royalty Free Stock Photos
Author: Wojpra

Explore more commercial options: More Caution Stock Illustrations & Vectors | More Caution Stock Video Footage