Updated

It's been more than three decades since Virginia State Trooper Johnny Rush Bowman was stabbed to death at his home outside the nation’s capital, but federal investigators are hopeful a new reward -- and a plea from Bowman's daughter -- could finally lead authorities to the officer's killer.

Bowman was killed when he answered a doorbell in the early-morning hours of Aug. 19, 1984 at his home in Manassas, Va., located about 30 miles outside of Washington D.C. Bowman was stabbed between 40 to 45 times by an unknown assailant as his young daughter, wife, brother, and sister-in-law were in the home with him.

The FBI on Tuesday announced the agency is now offering a $50,000 reward for information that can lead to a break in the case, the only unsolved killing of a Virginia State Trooper in the commonwealth’s history.

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Virginia State Trooper Johnny Rush Bowman was stabbed between 40 and 45 times when answering the doorbell at his home in Manassas on Aug. 19, 1984. (FBI)

“This push for information is nationwide,” said First Sergeant Michael B. Elliott with the Virginia State Police Bureau of Criminal Investigation. “With as much time that has passed, people have potentially moved to other parts of the country. If they have knowledge, I hope they will do the right thing and come forward.”

The attacker or attackers left behind sunglasses, a wig, and a construction hard hat. Even with advances in DNA testing and other forensic technology, investigators have not been able to track down any substantial leads after reexamining evidence from the crime scene.

The killing of the 31-year-old off-duty officer spurred one of the most extensive and costly murder investigations in the history of the Virginia State Police, with more than 3,000 people in 41 states interviewed by police, the Washington Post reported at the time. The FBI said it became involved in the case because the murder is considered a line-of-duty death.

Bowman's daughter, who was two years old at the time, was awakened in the early-morning attack that ended her father's life. Now an officer with the Manassas Police Department, Nikki Bowman said in a video released by the FBI that her father's memory inspired her to pursue a career in law enforcement and drives her need to find resolution in his case.

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Virginia State Trooper Johnny Rush Bowman and his daughter, Nikki Bowman. (FBI)

"Thirty-four years is a long time of waiting. My life is a constant struggle. Every day is hard, and I think it’s time for the roles to be reversed," she says. "Their life should be hard. You need to own up to what you’ve done. I should be able to live happily after this but I can't do that without answers."

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Nikki Bowman, who is not part of the investigative team, says that she will continue to "advocate the case" while encouraging anyone who may know about what happened to her father to come forward.

"I would find it very hard to believe that there’s not someone or multiple people that know what happened that day," Bowman says in the video. "Whether it was by word of mouth, they were there, someone that was there told them, but somebody knows something."

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Nikki Bowman, now an officer with the Manassas Police Department, said that she just wants answers for her father's killing. (FBI)

In the video, the officer said she remains hopeful someone will finally speak up.

"I’m thankful to everybody that’s still pursuing the case and taking time to continue investigating, continue following leads, trying to find more leads," she says. "At the same time, 34 years is a long time, and each year that passes it gets a little bit more difficult. I just want answers."

Anyone who may have information about the case is contact the FBI at 1-800-225-5324 or Virginia State police at 703-803-2676.