UNIONDALE, N.Y. — A junior at Hofstra University and an armed intruder were fatally shot during an overnight house break-in next to the campus, police said Friday. The woman’s twin sister was also in the house at the time but was unharmed.
It wasn’t clear who fired the fatal shots or how many rounds were fired, but authorities said police were involved in the shooting.
The crime cast a pall over the university, which had been gearing up for commencement ceremonies this weekend.
Hofstra identified the slain student as Andrea Rebello, 21, of Tarrytown, N.Y. Her sister, Jessica, was also in the house but was not injured, police said.
The two sisters, another woman, and a man were inside the two-story rental house when the gunman, wearing a ski mask, forced his way in, according to Kenneth Lack, Nassau County deputy inspector.
The intruder allowed the third unidentified woman to leave, and she called 911.
A law enforcement official with knowledge of the investigation told the Associated Press that the woman called 911 from near an ATM.
The official was not authorized to discuss the investigation publicly and spoke to the AP on condition of anonymity.
Victoria Dehel, who lives four houses away, said she heard what sounded like fighting. At first she ignored it, figuring it was from rowdy students coming home from a bar.
Suddenly, ‘‘This girl was shrieking,’’ followed by loud bangs just seconds later.
‘‘It didn’t sound good at all,’’ Dehel said. ‘‘I turned to my boyfriend and I said, ‘I think someone just got murdered.’ It was awful.’’
The university sent a text alert to notify students and staff.