Two senior Asian American women waiting at a bus stop in San Francisco were stabbed by a man with a knife on Tuesday afternoon, May 4 (U.S. time).

Police have arrested the suspect, a 55-year-old man.

The incident has not been ruled a hate crime, the police said, as investigations are ongoing.

One woman is in her 60s, while the other is 85.

They were taken to a hospital and in stable condition as of Tuesday night.

A witness at a nearby flower stand who saw the incident told ABC7 that she saw the man stab one of the women.

"Her back was turned and all I see was the feathers coming out of her jacket, so I'm very sure that she got sliced," the witness said.

Charges could be filed as soon as Friday, the San Francisco district attorney said.

This attack is the latest in a string of violent attacks on Asian Americans.

Donations sought for older woman

The grandson of the 85-year-old woman, Drew Eng, told BuzzFeed News one of the woman is Chui Fong Eng.

In a GoFundMe raising money for medical expenses, Drew's sister Victoria said their grandmother was waiting at the bus stop to go home when she was "stabbed with a long knife in her right arm" and the knife had "entered into her chest".

"These Asian hate crimes need to stop. Our hearts go out to all those who have been injured, killed, or affected by this wave of racist crimes toward the Asian community," Victoria said.

"San Francisco is my home and my grandma’s home. We need to feel safe where we live and not in constant fear."

String of attacks on Asians

The stabbing in San Francisco is one of at least four attacks on Asian people in several cities this week alone.

On Sunday, May 2, a man attacked two Asian women in their 60s, who are sisters.

They were closing a Baltimore liquor store at night.

The man struck them in the head with a cinderblock, and the victims tried to fight him off.

In New York City on the same Sunday, two Asian women were accosted by an attacker who yelled at them to remove their masks, before hitting one on the head with a hammer.

Before this latest knife attack, an Asian man walking his toddler in a stroller in San Francisco was shoved to the ground by a stranger and beaten outside a grocery store.