Mount Holly, N.C. — Two cousins have been charged in the death of a University of North Carolina-Charlotte student from Chapel Hill, police said Friday.

Mark Bradley Carver, 40, of 113 Carver St. in Gastonia, and Neal Leon Cassada Jr., 54, of 210 Plantation Drive in Mount Holly, were charged with first-degree murder and felony conspiracy, according to arrest warrants filed at the Gaston County magistrate's office.

Irina Yarmolenko, a Chapel Hill High School graduate, was found dead on the banks of the Catawba River in Mount Holly on May 5. Police said the 20-year-old had been asphyxiated.

Carver and Cassada are scheduled to appear in court on Monday. Authorities said they will not face the death penalty.

Saying they didn't want to jeopardize their investigation, Mount Holly police provided no details about a possible motive or what led to the arrests. A $15,000 reward has been offered in the case, and it was unclear whether a tipster provided a break in the case.

In an interview with WBTV News Friday evening, Carver maintained his innocence. He said that he gave police DNA samples that investigators said they matched to DNA found in Yarmolenko's car. He said he doesn't know how his DNA got there.

“I’ve never met the girl in my life,” Carver said.

Police said they found Yarmolenko’s 1998 Saturn at the edge of the Catawba River, facing the water. The car had traveled several yards down a steep embankment and struck a tree stump at the water’s edge, damaging the front end.

Yarmolenko’s body was found on the ground next to the driver’s side door, police said.

Carver said that he and his cousin were fishing at Catawba Lake the day Yarmolenko’s body ended up there, but had nothing to do with her death.

“I don’t know why they hadn’t looked for somebody else. I ain’t the one that done it,” Carver said.

He expressed hope that the true killer would be found.

“I hate it happened. I want them to catch the right one," Carver added. "I feel sorry for them because I’ve got children of my own."

Yarmolenko’s family drove from Chapel Hill to Gaston County Friday to meet with investigators and discuss the case.

"This thing that has happened has always just sort of eaten at us," said Yarmolenko's brother, Pavel Yarmolenko.

“For me personally, I feel a little easier knowing that the people who did this would ultimately answer to justice,” Pavel Yarmolenko said.

In the hours before her death, security cameras showed Irina Yarmolenko stopping at a coffee shop and making a donation at a Goodwill store in Charlotte.

Police said data retrieved from a data recorder in her Saturn showed someone was sitting in the driver’s seat when the car went down the embankment.

The Saturn was going about 15 mph down the embankment when it hit the stump, and the driver’s-side seat belt was engaged at the time, police said. The recorder also revealed that someone started the car at the scene.

Pavel Yarmolenko said his younger sister's spirit will live on in her passion for the arts.

"She knew how to make people smile," he said. "When people read her poetry and read whatever else she'd been writing, I think they'll get to know a really incredible person."