Updated

A suspect in the slaying of a University of North Carolina student leader was charged Thursday with the killing of a graduate student at Duke University, authorities said.

Police charged Lawrence Alvin Lovette Jr., 17, of Durham, with first-degree murder in the death of Abhijit Mahato hours after he surrendered in the death of UNC student body president Eve Carson.

It was not immediately clear how, or if, the two cases were connected. The Duke and UNC campuses are less than 10 miles apart, and it appeared robbery was involved in both deaths. Mahato's wallet and cell phone were gone, and authorities have said the two suspects in Carson's death were caught in surveillance photos trying use her ATM card.

Mahato, 29, originally of Tatangar, India, was a doctoral student in computational mechanics. He was found shot to death inside his apartment a few blocks south of Duke's campus in January. One arrest had already been made in his death: Stephen Lavance Oates, 19, is being held without bond on charges of murder and of robbing 18 people, including Mahato.

Police had been searching for suspects in Carson's death since the 22-year-old was found lying in a street about a mile from the Chapel Hill campus last week. The biology and political science major from Athens, Ga., had been shot several times, including once in the right temple.

Carson's death led to a massive outpouring of grief at North Carolina. The school's Board of Trustees offered a $25,000 reward for information leading to an arrest in her death, and police received hundreds of tips.

Authorities focused their investigation on several ATM and convenience store surveillance photos that showed a suspect trying to use Carson's card.

Lovette and Demario James Atwater, 21, were charged Wednesday with first-degree murder in the Carson case. Atwater made an initial court appearance Wednesday. Shackled at the ankles and waist, and with a public defender at his side, Atwater only whispered "yes" when asked if he understood the charges against him, and was ordered held without bond.

Oates' attorney, Brian Aus, did not immediately return a message seeking comment. The Orange County Public Defender's office said Atwater and Lovette had not yet been assigned attorneys.

Police believe Lovette was pictured in two photos taken at the ATM, driving Carson's Toyota Highlander while Atwater is in the back seat. Police also believe Atwater was the suspect shown trying to use Carson's ATM card inside a convenience store. Authorities haven't said if money was successfully removed from the account.

Lovette surrendered around 4:16 a.m. Thursday after authorities received a tip around midnight he was inside a Durham home, police Lt. Robert McLaughlin Jr. said.

Lovette also was charged with robbery with a dangerous weapon in Mahato's killing. Separately, he was charged Thursday with misdemeanor larceny, communicating threats, contributing to the delinquency of a juvenile and common law robbery.