Man Stabbed to Death in Dispute after not Saying 'Thank You' in a Brooklyn Smoke Shop!

NEW YORK -- A man was killed inside a Brooklyn bodega on Tuesday night after a fright broke out, apparently over one man not saying "thank you" to the other.

That's according to a man who witnessed it all, the worker behind the counter, CBS2's Dave Carlin reported Wednesday.

The deadly argument was caught on video inside and outside a store on 4th Avenue in Park Slope. Witnesses said the violence started over, of all things, an unlikely dustup over good manners.

The footage shows the beginning of the confrontation between a man in a white t-shirt, who wound up stabbed to death, and a man wearing a backpack, possibly for a job delivering food.

The video is silent, so you cannot hear what they are saying, but Kharef Alsaidi, a worker at Park Slope Convenience, which sells candy and smokes, told Carlin the man in the white shirt held the front door open for the man with the backpack, and then criticized the man for failing to say thank you.

At one point on the video, the man wearing the backpack seems to start to leave and a man in white appears to push his bike and slap him. Then, the man wearing the backpack pulls out a knife and uses it.

Alsaidi told CBS2 what happened next, as the fatally injured man in white returned to the shop.