Hong Ri Wu, 56, of San Francisco, was taken into custody Sunday evening at a shop at 269 Jefferson St., where he allegedly shot Qiong Han Chu, a 30-year-old man, and Feng Ping Ou, a 30-year-old woman, police said.
Wu was in San Francisco Superior Court to be arraigned this morning, but the arraignment was postponed until Tuesday.
He did appear in court and said he couldn't afford a lawyer. The public defender's office was assigned the case.
The shootings were reported at 8:20 p.m. Sunday at the store, which sells souvenirs and luggage, according to police.
Police said Wu, who worked at a nearby competing store and knew the victims, walked into the store and allegedly shot Chu and Ou. The victims, both San Francisco residents, were pronounced dead at the scene.
"It's a dispute between merchants regarding the selling of similar items," police Lt. Troy Dangerfield said.
Interim police Chief Jeff Godown called the shootings an "isolated incident." A gun believed to be the murder weapon was recovered at the scene, he said.
Wu was booked into San Francisco County Jail Monday morning on two counts of murder, according to the sheriff's department.
Police are hoping that two tourists, a man and a woman who were in the store at the time and spoke briefly with police but did not leave their contact information, will come forward.
Anyone with information about the case is asked to contact homicide Inspector Martin at (415) 553-9183 or the anonymous tip line at (415) 575-4444.