An MTA officer shot and killed a suspect who stabbed him in the eye at a Queens Long Island Rail Road station Wednesday morning, police said.

Officer John Barnett, 45, was stabbed on the sidewalk under the tracks at the Sutphin Boulevard and Archer Avenue station in Jamaica while he was on patrol at about 9:30 a.m. The officer then shot the suspect, police said.

Barnett suffered a "devastating eye injury," according to the surgeon who operated on him for four and a half hours. The knife nearly severed his eyeball in half and it will be at least 48 hours until doctors can offer a prognosis on the officer's vision in his left eye, the surgeon said.

Both the officer and the suspect were taken to Jamaica Hospital, where the suspect was pronounced dead. Officials said he was shot three times -- once in the jaw, chest and hips. He has been identified as 46-year-old Edgar Owens of the Bronx. Authorities said he has a lengthy criminal history.

Barnett, who has been with MTA police for more than 10 years, was conscious and talking before he was taken into surgery. Agency officials said he did "exactly what was expected" from MTA police officers in similar situations.

"In a split second, confronted with a violent individual who posed a threat to everyone around him, he took action without regard to his personal safety. We are all in awe of his bravery," MTA Chairman Joseph Lhota said.

Police sources say the suspect's knife was recovered at the scene. The MTA said Wednesday was the first time Barnett fired his weapon.

Officials said the incident was unprovoked. Investigators are reviewing security tape from the train station. Train service was unaffected.

The investigation is ongoing.

Barnett's mother and 12-year-old son are at the hospital. Gov. Andrew Cuomo said he also met with the officer before he went into surgery.

"Today we are reminded once again of the bravery and sacrifice of our men and women in law enforcement, and the many dangers that accompany the important job of keeping our state's residents safe," the governor said.

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