Mechthild Schröer , 50, of Minden, North Rhine-Westphalia was walking with her husband in the popular Union Square plaza around 9 pm on Sunday when she was caught in the crossfire between two groups and shot, according to broadcaster KTVU.

“Staff at the St. George Hotel where the couple was staying told KTVU that Schröer and his wife checked into the hotel only hours before the shooting,” the broadcaster reported. “It was their first trip to San Francisco and they were in the city to celebrate their wedding anniversary and the shooting victim’s birthday.”

The woman died of her injuries at a California hospital. Two other people were injured. On Monday night police said they had charged 18-year-old Phillip Stewart with murder.

Shortly before that, the late woman’s husband Stefan left the St. George hotel to board a flight back to Germany, the broadcaster said.

“On behalf of our entire City, I offer my deepest condolences to the family and friends of Mechthild Schröer, who died needlessly from this senseless violence,” Mayor Gavin Newsom said in a statement on Monday.

According to KTVU, the shooting, along with another in the area the same night, was part of a rash of nightclub-related violence in the city.

In response, Mayor Newsom signed an order on Monday giving the San Francisco Entertainment Commission the right to revoke nightclubs’ licences for problem establishments.