The victim was identified as store worker 27-year-old Melyda Corado by her brother, Alberto Corado. He said the suspect also released some people himself. The episode began with a family dispute in Newton Division.
Police Chief Michael Moore earlier said the man shot his grandmother seven times and she had undergone a series of surgeries at a local hospital.
The suspect then left the area in the grandmother's vehicle, taking the other female with him, authorities said.
The grandmother, whom relatives identified for ABC News as Mary Elizabeth Madison, was at a hospital in stable condition on Sunday. Shocked customers in the parking lot watched the suspect engage in the gun battle with police.
The suspect fled in a 2015 Toyota Camry and during a police pursuit, the suspect fired multiple rounds at officers, Lopez said. An employee of the Associated Press who lives in the area reported seeing a vehicle crashed into a utility pole outside the store.
As CrimeOnline previously reported, the suspect in his late teens barricaded inside the store, is apparently telling police that he'll start shooting if they try to enter the store.
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Police said the older woman was the suspect's grandmother, and he was driving her auto when he wrecked it near the Trader Joe's.
Police said Gene Evin Atkins, 28, was the man who held officers at bay for three hours on Saturday and engaged in a gunbattle in which the store manager was killed when she was caught in the crossfire. Those people included the suspect, a 20-year-old woman, 12-year-old boy, 41-year-old woman, 71-year-old woman and an 81-year-old woman.
- Eighteen ambulances and more than 100 firefighters are at the scene of the incident, Los Angeles Fire Department spokesman David Ortiz said. "Employee says blood was all over the floor, unclear from where", he wrote. The standoff made for a chaotic scene in the Silver Lake area. He later deleted the tweet.
President Donald Trump earlier tweeted that he was monitoring the standoff "very closely". "Active barricaded suspect. L.A.P.D. working Federal Law Enforcement".
The investigation was ongoing. A makeshift memorial of flowers, candles and notes grew on the sidewalk outside of the store on Sunday.
A manager at Gelson's Market, across the street from Trader Joe's, said people inside the market heard shots fired outside. Our focus is on doing whatever we can to support them at this time.