By Brad Segall

HOLLAND, Pa. (CBS) — This month marks six years since attorney Eric Birnbaum was shot and killed in the parking lot of his law office in Holland, Pa., and law enforcement authorities are still hoping for that hot tip that can help them break the case.

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It was February 11, 2009, and Birnbaum had just arrived for work.  He was talking with a co-worker in the parking lot on Buck Road when a man ran up, fired a shot into the back of Birnbaum’s head, and fled.

The only description available was the man wore sunglasses and dark cap.

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Bucks County prosecutor Matt Weintraub doesn’t believe this was a random killing.  He is sure there was some connection between Birnbaum and the shooter.

“I have no doubt of it,” Weintraub tells KYW Newsradio.  “I believe there are people out there that can help us not only solve this case but bring this killer to justice.”

The trail of evidence remains cold, and Weintraub calls that frustrating.  But, he says, they are not giving up.  Officials continue to publicize the case through digital billboards along area highways.  The reward money stands at more than $20,000.

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