Authorities investigating vandalism at Yosemite National Park

YOSEMITE NATIONAL PARK, Calif. (KFSN) -- Officials are asking for the public's help after parts of Yosemite National Park were vandalized.

Pictures from the park show blue and white graffiti -- some which says "Fresno."

On May 20, park rangers responded to reports of vandalism on the Yosemite Falls Trail by setting up a trail block to identify potential suspects.

The next day, the rangers assessed the damage and found about 30 areas along the trail spray painted with graffiti.

Authorities are asking anyone on the trail to the top of Yosemite Falls between 6 and 11 pm on May 20 and saw people carrying spray paint, tagging, or have photos of the vandalism to submit a tip on the National Parks website.