The body of a candidate for mayor of Clarksdale, Miss., was found about 15 miles west of town Wednesday, and a person was in custody, sheriff's officials said.

Authorities had been searching for Marco McMillian, 34, since Tuesday morning, when his sport-utility vehicle was involved in a head-on collision in Coahoma County, the county sheriff's office said in a statement.

But McMillian wasn't in the vehicle, authorities said. The driver of his vehicle, identified as Lawrence Reed, 22, of Clarksdale, was airlifted to a hospital in Memphis, Tenn., about 60 miles away, NBC station WMC of Memphis reported.

There was no immediate report on the cause of death, according tothe Coahoma County coroner's office.

The sheriff's department declined to say whether Reed was the "person of interest" who was taken into custody or whether the action was taken in connection with McMillian's death or as a separate part of the accident investigation. The department said no further information would be immediately provided "due to the fact this is an ongoing investigation."

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McMillian — who was chief executive of MWM & Associates, a consultant to nonprofit organizations — was widely noted as one of the first openly gay candidates for public office in Mississippi.

His campaign spokesman, Jarod Keith, told the Clarion-Ledger newspaper of Jackson, Miss., that McMillian's sexuality was never an issue in the campaign.

The Gay & Lesbian Victory Fund, a national advocate for gay political candidates, tweeted Wednesday:

"Our hearts go out to the family and friends of Marco McMillian, one of the 1st viable openly #LGBT candidates in Mississippi."

In a statement Wednesday, McMillian's campaign said: "Words cannot describe our grief at the loss of our dear friend, Marco McMillian. The shocking news of Marco's death is beyond difficult for us to process."

Two of McMillian's opponents — who, like McMillian, are Democrats — said they, too, were shocked and saddened by the development.