The Adopt-A-Highway sign heralding a stretch of road occasionally cleaned by a California atheist group has been defaced for a second time in the last three weeks.

The most recent act of vandalism to the sign sponsored by Atheists United San Luis Obispo occurred last week. An unknown perpetrator sawed the sign off its posts and painted over the first letter and the last letters of “Atheists.”

Thus, after the vandalism, the all-caps word “ATHEISTS” was transformed to “THEIST.”

Members of the heathen group say they refuse to be intimidated by someone causing damage to their highway sign on the southbound side of Highway 101 near Atascadero, Calif.

“Despite this act of vandalism, AU SLO remains dedicated to making it acceptable to be a non-believer in this county,” group president Steven Arkowitz said is a press release sent to The Daily Caller.

Citing the atheist group’s value to locals who refuse to believe in God, Atheists United San Luis Obispo has declined an offer from the California Department of Transportation to move the sign.

The executive director of Washington, D.C.-based atheist group United Coalition of Reason, Jason Heap, expressed frustration that California highway department officials would not take a strong stand on the part of atheism.

“I am disappointed that Caltrans has taken this attitude towards the nontheistic community of San Luis Obispo, offering to move their Adopt-a-Highway sign, rather than to address the real issue at hand, which is the repetition of uncivil acts towards non-theists,” Heap said in a statement. “The tax money used to pay for highway signs are not sacred to any one particular sincerely-held belief. These continued acts of vandlism [sic] makes it clear that some people in our pluralistic society believe it is acceptable to harrass [sic] and victimize certain communities with whom they disagree.”

Atheists United San Luis Obispo is vital to the local community, group members insist.

“Almost every week we have new members join AU SLO and tell us how happy and relieved they are to find our group,” Arkowitz claimed. “We are proud of the positive work we do in our community and the sign represents a small part of that work.”

Upcoming events sponsored by Atheists United San Luis Obispo include participation in a Los Angeles AIDS Walk, a burial service for a former co-president of the organization and two general meetings.

Atheists United has been intermittently sprucing up the stretch of road near the sign on Highway 101 for nearly 18 months.

The previous incident of vandalism occurred on Sept. 19 when someone spray-painted a big, red letter “X” on the sign, reports Paso Robles Daily News, an area newspaper.

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