CHAPEL HILL - Police now think a second person may have been in the vehicle driven by a man they say was trying to use slain UNC-Chapel Hill student Eve Carson's ATM card.

Black-and-white photographs distributed at a Saturday news conference show what looks like a figure in dark clothing in the back seat of the vehicle. What looks like a person's chest and right shoulder can be seen between the driver's seat and head rest.

"We believe there may have been a second person in the vehicle," Chapel Hill Police Chief Brian Curran said Sunday evening.

Police received the surveillance images electronically and are waiting for the actual footage to be sent by FedEx, Curran said.

"We're looking for original source video," he said.

Tips came in over the weekend after police released the photos of the driver in what they said could be Carson's 2005 Toyota Highlander, authorities said. But as of Sunday night, no arrests or other developments had been announced in Wednesday's slaying of the student body president.

"There's somebody out there, probably more than one, who knows who this guy is," Curran said of the driver in the photos. "Those are the people that we're depending on right now."

Police have described the driver only as a black male in his late teens or early 20s, wearing a hooded sweatshirt, gloves and a cap with a star on it.

They have said the photos were taken by a surveillance camera at a Chapel Hill area ATM, but they have not said where the machine is or when the pictures were shot.

The UNC-CH Board of Trustees has pledged a $25,000 reward for information leading to an arrest in the case.

District Attorney Jim Woodall, whose jurisdiction includes Orange County, said he had gotten regular updates from investigators.

"Most people, their first and their natural reaction in a case [is], 'Oh, you've got a photo, you've got something great,' " Woodall said. "You've always got to remember, somebody's got to come forward and say, 'Oh, I know who that is' and be right about that.

"Oftentimes a reward is the thing that more people react to, frankly," he added.

Woodall emphasized that tips can be made anonymously.

"It would be obviously much better if a person is willing to come forward and give their name to the authorities," he said. But investigators "would rather have anonymous information than no information at all."

Police have called the man they say was using Carson's ATM card "a person of interest." They have stopped short of calling him a suspect in her death.

The body of Carson, 22, was found in the Hillcrest neighborhood northeast of campus about 5:15 a.m. Wednesday with gunshot wounds, including one to the head.

A memorial service was held Sunday in her hometown of Athens, Ga.

Police ask anyone with information in the case to call Crime Stoppers at 942-7515 or to go to www.crimestoppers-chcunc.org.

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