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Andrea Rebello Update: Police officer's bullet killed Hofstra University student during standoff, cops say

Hofstra student Andrea Rebello, 21, was shot and killed by a police officer's bullet in an attempt to rescue her from an armed intruder. CBS News

(CBS/AP) NEW YORK - Hofstra University student Andrea Rebello was killed by a police officer's bullet after a masked intruder held a loaded gun to her head in a Long Island home and then took aim at the officer, Nassau County police said.

PICTURES: Andrea Rebello

Rebello and the intruder were both killed after a split-second decision by the Nassau County police officer, authorities said. Police said Rebello was being held in a headlock by a masked intruder when the officer fired eight times, one shot hitting Rebello in the head.

The standoff took place early Friday in the home near the Hofstra University campus after authorities responded to the report of a home invasion robbery. Police have identified the suspect as Dalton Smith.

"The big question is, how do you know, when someone's pointing a gun at you, whether you should keep talking to them, or shoot?" said Michele Galietta, a professor of psychology at the John Jay College of Criminal Justice who helps train police officers. "That's what makes the job of an officer amazingly difficult."

Rebello's life ended in the seconds that forced the veteran police officer to make a fatal decision, but the questions surrounding the student's death are just beginning, along with an internal investigation by the Nassau County Police Department.

With a gun pointed at her, Smith "kept saying, `I'm going to kill her,' and then he pointed the gun at the police officer," according to Lt. John Azzata.

The officer acted quickly, saying later that he believed his and Rebello's life were in danger, according to authorities.

Police tactical manuals are meant to assist officers in making the best decision possible, but in the end, "they're not 100 percent foolproof," Galietta said. "In a situation like that, you can follow procedure, and it doesn't mean it comes out perfectly."

Hofstra student John Kourtessis told the New York Post that he'd gone to a bar with Rebello and a few other friends to celebrate the end of school. When they got back to Rebello's house, he said she asked him to move his car and he went upstairs to get his keys.

When he came back down, he said, Smith was there. He said Smith kept talking about "the Russian guy," insisting the house's residents owed a Russian man money and that he was outside waiting, according to the report.

"He was saying . . . that he just needed us to cooperate. I said, `Listen, we have all this money here."'

Kourtessis said the students offered Smith computers, jewelry and other items from the house but that Smith kept demanding more money.

The officer who fired the shots is an eight-year NYPD veteran and has been with Nassau County police for 12 years.

He is now out on sick leave, according to officials.

Procedurally, the Nassau County district attorney's office would determine whether an officer's use of deadly force was justified, O'Donnell said. A spokesman for the district attorney's office did not respond to a request for comment Saturday night.

According to CBS New York, Hofstra University President Stuart Rabinowitz reflected on the young woman's tragic death during the graduation ceremony Sunday.

"Our community's collective grief, our community's sorrow, over the senseless and tragic death of a very young member of the Hofstra family"

Students honored Rebello, a 21-year-old public relations major, by wearing white ribbons at their graduation ceremony.

Rebello's funeral is scheduled for Wednesday in Westchester County, north of New York City.

Complete coverage of Long Island student's home invasion on Crimesider