A man was wounded Thursday in a shooting near Golden Gate Park.
No arrests have yet been made.
She said she started yelling, 'It's actually a gun, it's actually a gun!' to get people's attention.
Police say three people were shot and transported to hospitals but didn't release other details.
Witnesses saw several people speeding away from the park in a auto, a police spokeswoman told SFGate.
Breaking - 3 people shot at Dolores Park in SF. Hatter said he "went up there to mediate and make sure everything was OK and nobody was fighting".
As he approached, someone shouted "They're strapped, bro!", meaning they had guns. Hatter's version of events were corroborated by multiple unnamed witnesses, according to the Chronicle.
Hatter says two people directly behind him were struck by bullets.
"I normally can handle (myself) well in these situations, but I was pretty sure I had just lost my life", Hatter said.
After the shootings, witnesses saw a vehicle speeding away with a group of people inside, according to police spokeswoman Grace Gatpandan.
Then she saw a man holding a gun. The victim with the emergency responders was covered in many bandages and "not looking good", according to the Chronicle. The park was packed with families, children and tourists when the gunman or gunmen opened fire on the pedestrian bridge off Church Street around 3 p.m.
She says it was a terrifying moment because people were not reacting, possibly thinking the blasts were fireworks. People began to run after realizing that it's an actual gunshot.