Juan Sanchez, 43, was stabbed and killed on August 31, 2007, at 10 United Nations Plaza in San Francisco. He was reportedly standing in the area when an unknown assailant approached and attacked him with a large knife; witnesses at the scene identified a single suspect but provided no detailed description that led to an arrest.

The San Francisco Police Department classified the death a homicide and the case is unsolved and cold. Investigators say the location has seen other violent incidents, which has complicated collection of clear witness information. The Mayor’s Office has authorized a $10,000 reward for information leading to an arrest and conviction.

Anyone who knows anything about what happened that night is asked to contact the San Francisco Police Department Homicide Detail or submit an anonymous tip. What did readers in that area see or hear that evening?