CORONA ( — A freeway message sign in Corona that was reprogrammed to display a “Vote Donald Trump” slogan was being investigated as an act of vandalism, but so far had turned up few leads, authorities said Monday.

California Highway Patrol investigators were trying to figure out who might be responsible for the sign, which is stationed at Ontario Avenue and northbound Interstate 15 and was tampered with sometime Thursday, according to the Riverside County Transportation Commission.

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But the investigation into the Christmas Day hacking episode was slow to get going because of the holiday downtime, according to CHP Officer Marcelo Llerena.

“I only heard about it today,” Llerena said.

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Instead of flashing a message regarding a detour related to construction work on I-15, the sign was changed to read: “Inland Empire Supports Donald Trump. Merry Xmas. Vote Donald Trump.”

A couple heading home from an outing Christmas night saw the message and stopped to videotape it. The clip had received more than 457,000 views as of Monday afternoon and had been re-posted by multiple people on YouTube.

The sign was immediately changed to its original detour message after the agency was alerted to what had happened, RCTC spokeswoman Eliza Echevarria told City News Service.

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