Federal and local investigators have interviewed individuals identified as potential targets of spray-painted racial slurs, curse words, insults, and wannabe gang-related graffiti discovered earlier this week at the popular Riverside Day-Use Area, a barbecue-picnic spot outside the town of Tuolumne on the North Fork Tuolumne River.

They’ve also collected a spray paint can cap found at the defaced recreation area as evidence, and they intend to send it to the federal Department of Justice for fingerprint analysis if there are any fingerprints located on the cap, a spokesperson for the Tuolumne County Sheriff’s Office said Thursday.

Whoever did the vandalism left white spray paint on public picnic tables, a grill, a metal bear-proof recycling and trash container, and paved walkways at the federally managed day-use area, which is part of the Stanislaus National Forest and is in an area known to locals as Basin Creek. The U.S. Forest Service is the lead agency investigating who is responsible for the graffiti storm that has outraged many Mother Lode residents and visitors.

A few juveniles have seen a snapchat video of the damage, but so far it’s just speculation on who may have had something to do with it, Sgt. Andrea Benson of the Sheriff’s Office said. No arrests or citations had been made as of Thursday afternoon.

A deputy spoke to individuals named in the graffiti storm and identified on social media as potential targets of whoever sprayed the foul-mouthed threats, Benson said. The information has been passed on to the Forest Service.

“The snap chat showed the graffiti but not anyone actually committing the crime itself,” Benson said. “All leads and information will be followed up on. Our deputy received two calls with leads initially and that is all we have received. USFS have been updated with any information the deputy received and will be following up on their investigation.”

Diana Fredlund, a spokesperson for the Stanislaus National Forest and the Forest Service, said they have one law enforcement officer investigating and working with the Tuolumne County Sheriff’s Office. She said she couldn’t comment on active investigations.

Tuolumne County Sheriff’s Office logs show a vandalism report at 8:01 p.m. Tuesday. It says in part, “Occurred at Basin Creek on Buchanan Road/1N01, in Tuolumne. Spray paint graffiti all over the area. A lot of people on Tuolumne Incident Feed are saying that two females posted the 594 on snapchat once they were done . . . ”

Penal Code 594 PC is California's vandalism and graffiti law and it includes monetary, misdemeanor and felony penalties.

Fedlund said Wednesday that Forest Service workers inspected and prepped the picnic area on the North Fork Tuolumne River for the summer season in March, and the gates were opened for public use on April 1.

The graffiti was discovered Monday morning this week and Forest Service workers closed the gates, Fredlund said. She added that the Forest Service expects to reopen Riverside Day-Use Area as soon as the site is cleaned.

Fredlund said she is trying to let people know that anyone who wants to volunteer to help with the graffiti cleanup can meet Forest Service workers at the Riverside Day-Use Area, three miles east of Tuolumne on Buchanan Road, at 9:30 a.m. Friday. Helpers should bring their own gloves and long-sleeved shirts, water and snacks. Staff with the Forest Service will provide materials and equipment.

Contact Guy McCarthy at gmccarthy@uniondemocrat.com or 588-4585. Follow him on Twitter at @GuyMcCarthy.