Deputy Clay Grant Jr. was off-duty and picking up a couple of household items from Target when customers started screaming.
He says he quickly saw why: A woman was running down the cosmetic aisle with a knife in each hand.
Layla Trawick, 34, had just stabbed four people, including a woman holding a baby, slashing at shoppers in an apparently random attack at the busy store Monday, authorities allege.
Grant grabbed his duty weapon, identified himself as a sheriff's deputy and ordered the woman to drop the knives, he said. She ran away and he followed her from aisle to aisle before she surrendered.
"She finally dropped her knife, and I was able to place handcuffs on her," Grant said.
The Target store is on the second floor of a shopping center at a busy West Hollywood intersection. Shoppers streamed down the stairs and away from the building in a panic.
"People were really scared," said Rachelle Calello, a makeup artist who works in a cosmetic store next to Target. "Who knows if she has a knife or something else?"
A mother holding her baby was stabbed in the neck and was taken to the hospital, where she was in stable condition, Los Angeles County sheriff's spokesman Steve Whitmore said. The baby was unhurt and all four victims were expected to survive.
One witness said she was shopping for a Mother's Day card when she heard someone screaming, "There is no witness protection program!" as chaos broke out in the store.
Katy Winn, a freelance photographer from West Hollywood, said the woman was yelling at the top of her voice.
"I think I heard (the deputy) telling her to drop to the floor. That's when things got really chaotic and started falling over," Winn said.
Grant was wearing a white T-shirt, camouflage shorts and running shoes so several shoppers mistook him for a gunman, adding to the sense of panic, officials said.
Calmly recounting the events at a news conference Monday, Grant said his training kicked in and he decided not to shoot because he didn't feel his life was in jeopardy.
"Her facial expression was someone who was lost, confused, didn't know exactly where they were," Grant said.
Trawick was arrested with the help of private security guards and held on $1 million bail on suspicion of attempted murder. It was not immediately known if the Antioch woman had an attorney.
Investigators were trying to determine whether Trawick got the knives in the store.
Associated Press Writer Raquel Maria Dillon in Los Angeles contributed to this report.
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