SAN FRANCISCO – Tuesday was grocery day for 85-year-old Chui Fong, who had taken a bus to San Francisco’s Chinatown that afternoon to buy groceries.

“She’s independent, very headstrong. If she has to do something, she’ll do it. It’s just her,” said her grandson Drew, who asked that we only use his first name.

She was waiting at the bus stop near 4th Street and Stockton Street Tuesday night when she and another 65-year-old Asian woman were stabbed to death.

“I was told the knife stole her lungs and chest. It was a really long knife,” Drew said.

She was rushed to the hospital when police said her injuries could be life-threatening.

After more than four hours in the operation, Drew said the family doctors said she would survive.

“She’s just a great woman,” he beamed.

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The 65-year-old woman was also taken to hospital with serious injuries, but according to the police, she should survive.

The attack occurred around 4:50 p.m. along busy Market Street when several onlookers watched in horror. The suspect was seen casually walking away before he was caught by SFPD on the 600 block on Eddy Street an hour later.

“You were familiar with this person,” said SFPD chief William Scott of the Tenderloin officials who made the arrest.

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Police identified the suspect as Patrick Thompson, 54, who has a criminal record and includes multiple charges such as assault with a deadly weapon and battery with serious bodily harm.

Chui Fong’s family set up a GoFundMe to pay for medical expenses.

Prosecutors said they expected to file charges Thursday.

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