Police say the suspect barricaded himself in the apartment on Franklin Street around 7:30 a.m. After a few hours, investigators declared the event a "critical incident." It was around 11:00 a.m. when the SWAT team raced to the scene.
Officers packed the building and investigators spent most of the day at the apartment, but learned few details about the man inside. They blocked off surrounding streets in the neighborhood and hostage negotiators tried to make contact by phone with the barricaded man.
"We're very concerned because someone has barricaded himself in his room. He's not making contact with the police. We're very interested his well being and safety as well as the other people who live in the apartment building," Sgt. Michael Andraychak said.
Just five blocks east of that location, at about the same time, a completely unrelated second incident occurred. San Francisco police responded to a noise complaint at the Grenada residential hotel on Sutter Street in the Tenderloin.
Someone, possibly a tenant, threw stereo speakers out the window of a seventh-floor apartment.
"Apparently, there's been lots of calls about noise complaints," Sgt. Troy Dangerfield said.
Police say when they went to investigate, a tenant pulled out a weapon and the officer fired. Authorities are not saying what kind of weapon the man had.
"The person displayed weapons to the officer and the officer fired," Dangerfield said. "It was a fatal shot to the victim."
Many of the hotel residents are seniors. One man said he heard the shots, about eight of them, from inside his room.
"Some police officers were there, three police officers. One of them was really shook up and she was saying to the others that she didn't know how many shots she fired. Then, they told me to get back in my room so I did," John Susoeff told ABC7.
The officer-involved shooting is being investigated by San Francisco police internal affairs, the department's homicide division, and the San Francisco district attorney's office.