A San Francisco woman has died after drinking poison tea from a Chinatown shop. The woman's death came more than a week after she and another man became critically ill from drinking toxic tea sold at the same establishment, prompting the city's department of public health to identify the store and warn residents not to consume tea purchased there. 

Yu-Ping Xie, 56, died Saturday after ingesting tea laced with Aconite, a lethal plant-based poison, San Francisco health officials said Monday. Xie and another victim, a man in his 30s, became immediately ill after consuming tea made from leaves bought at the Sun Wing Wo Trading Company, local news reports said

Read: Is Tea Bad For You? 2 Critically Ill In San Francisco After Consuming Herbal Tea

Health officials were working with the proprietor of the shop to identify the source of the toxin. Both people drank tea that was mixed in the store from several different ingredients, authorities said, adding that the shop was cooperating with the investigation. 

“The two patients each purchased different blends of medicinal teas that were put together for them at the shop,” health officials said in a statement. “The teas had several ingredients, and the ingredients that were common to both tea mixtures are currently being tested.”

The San Francisco Medical Examiner has been working to determine the official cause of death, the San Francisco Chronicle said. Both Xie and the other victim experienced weakness and abnormal heart rhythms requiring resuscitation within an hour of drinking the tea. A department of health spokeswoman said the man was treated and released after recovering from the illness brought on by the poisoning. 

While aconite has been used in Chinese herbal medicine for thousands of years, its flowers are highly toxic, the Chronicle said. However, the flowers were usually safe when processed.

There is no antidote for aconite poisoning.