Of the five San Francisco teens detained in the shooting death of Mechthild Schroer, 50, one has been arrested. Police have booked and charged 18-year-old Phillip Stewart, of San Francisco, with murder. The shooting erupted after a melee broke out at a private party held at a nearby club. Four other teens were arrested.

Schroer, if you recall, was killed on Sunday while walking in the theater district in front of her husband. She was visiting San Francisco while celebrating her 50th birthday and 25th wedding anniversary.

While some have expressed concern over guns and crime in San Francisco (most notably a German SFist commenter who expressed her outrage yesterday), Union Square and its surrounding areas could hardly be considered a war zone.