AUGUSTA — Maine’s secretary of state has sent letters to students at four universities telling them they need to register their vehicles in Maine and get Maine driver’s licenses if they want to continue voting in the state.

Secretary of State Charles Summers’ one-page letter was sent to 201 students who were part of his investigation into whether nonresident students who registered to vote in Maine had committed fraud.

Summers announced late last month that his office found no election fraud, but that 191 of the students who registered to vote in Maine did not have Maine driver’s licenses.

State law requires drivers who declare Maine residency to get a Maine license and register their vehicles within 30 days of moving to Maine, according to Summers’ letter. In all, he sent letters to students at University of Maine at Orono, the University of Maine at Machias, the University of Maine at Farmington and the University of Southern Maine, according to a department spokeswoman.

“If you are currently using an out-of-state driver’s license or motor vehicle registration, I ask that you take appropriate action to comply with our motor vehicle laws within the next 30 days,” Summers wrote. “If, instead, you are no longer claiming to be a Maine resident, I ask that you complete the enclosed form to cancel your voter registration in Maine so that our central voter registration system can be updated.”

Summers conducted his investigation over the summer following a request by state Republican Chairman Charles Webster just as a “people’s veto” referendum campaign was heating up to restore Maine’s election-day registration system and repeal a new law requiring people to register at least two days before Election Day. Mainers will decide Nov. 8 whether to keep or repeal the law.

University of Maine System spokeswoman Peggy Markson said it’s likely some students were upset after receiving Summers’ letter.

“That’s our concern — that it could be upsetting to them considering there was no fraud committed,” Markson said.