Updated at 10:10 a.m.: Revised with the new details from Collin College.

The city of Plano has beefed up security at polling locations after a man cut his hands on a Trump-Pence sign with blades hidden on it last week at a Collin College campus.

College police continue to sweep the campuses daily and haven't found anything suspicious since the incident, Collin College spokeswoman Lisa Vasquez said in an email Tuesday. The investigation is still open.

The man was dropping off a friend who was serving as an election worker about 6:15 a.m. Nov. 1 when he noticed a campaign sign for Republican presidential nominee Donald Trump at the Spring Creek campus of Collin College, 2800 E. Spring Creek Parkway, Vasquez said.

The man stopped as he left the campus to reposition the sign to the correct location because it was blocking the official polling site sign. When he did so, box-cutter blades attached to the Trump-Pence sign cut his hands.

The man chose to treat the minor cuts himself and not seek medical attention, Vasquez said.

The incident was reported to campus police and the Texas Rangers.

"All campaign signs on the college's campuses are being inspected, and any sharps found on signage will be removed," Vasquez said. "The college will be working with local election officials and both political parties to ensure safety."

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