On a routine April night, a man on a scooter rode away from the Queens restaurant where he worked making deliveries.
What the deliveryman, Zhiwen Yan, did not know as he made the dinner run was that an angry customer, who months earlier had demanded a refund after saying he had not gotten enough duck sauce with his order, was watching him leave the restaurant.
The man followed Mr. Yan to an intersection in Forest Hills, Queens. Then, as Mr. Yan waited at a stoplight, the man who had been trailing him approached and fired a single fatal shot into his chest.
The account of what happened that night was described by prosecutors on Thursday as they announced the indictment of Glenn Hirsch, 51, of Briarwood, Queens, on murder and other charges in Mr. Yan’s death.
Mr. Hirsch pleaded not guilty at an arraignment on Thursday in Queens Supreme Court. He was ordered held until a court date later this month. He faces up to life in prison if convicted.
“A petty dispute over a takeout order became an obsessive point of contention for the defendant who began to stalk and harass employees at the restaurant for months,” Melinda Katz, the Queens district attorney, said in a statement on Thursday.
Mr. Hirsch’s lawyer, Michael D. Horn, said the authorities had “arrested the wrong man.”
“Glenn Hirsch is only guilty of having an argument, according to the police, when his meal order was not made the way it was supposed to be done,” Mr. Horn said.
Through her lawyer, Mr. Yan’s wife, Eva Zhao, said in a statement that she was “relieved that someone has been arrested.”
“We are grateful to the N.Y.P.D. and have full confidence that the Queens district attorney will bring justice to Zhiwen Yan, a loving and kind husband, father, son, friend and community member,” she added.
Last November, months before the fatal shooting, prosecutors said, Mr. Hirsch had ordered food at Great Wall, the Queens Boulevard restaurant where Mr. Yan worked for over 20 years.
Mr. Hirsch was furious that night about not getting enough duck sauce packets with his dinner, prosecutors said. Even after workers handed him extra sauce, he insisted on a refund.
One worker refused, and Mr. Hirsch called the police. An employee told officers that the restaurant could not take back orders because of concerns about the coronavirus, prosecutors said. Mr. Hirsch then stormed out of the restaurant, according to a news release from the district attorney’s office.
For weeks after the episode, Mr. Hirsch continued to unleash his anger on Great Wall employees, damaging one employee’s vehicle with a knife in December, prosecutors said. When Mr. Yan and his co-workers confronted Mr. Hirsch, prosecutors said, he told them, “I have a gun” and “Be careful, this is the last time I’m going to tell you.”
About a month after that altercation, Mr. Hirsch showed up at the restaurant again, and pointed a gun at an employee who was shoveling snow, prosecutors said.
“How’s your car? Remember me?” Mr. Hirsch said, according to the news release. “I will kill your entire family.”
The worker rushed into the restaurant and called the police. When he went back outside, Mr. Hirsch was gone but the tires on a worker’s car had been slashed, prosecutors said.
On April 30, Mr. Hirsch dropped his wife off at work and then headed toward the restaurant, prosecutors said. He drove past it seven times between 7:30 p.m. and 9:30 p.m. before spotting Mr. Yan, 45, as he left to make the delivery.
Mr. Hirsch followed Mr. Yan to an address on 108th Street, where he dropped off an order, then to 67th Drive and 108th Street, where he then fatally shot him, prosecutors said.
Mr. Yan was taken to Elmhurst Hospital Center, where he was pronounced dead.
Mr. Yan, a father of three children, immigrated to the United States from Fuzhou, a city in southeastern China. He often delivered lunch orders to students at Kweller Prep Tutoring and Educational Services Inc., the owner, Frances Kweller, said.
“This is literally someone who we saw all the time,” said Ms. Kweller, who has helped raise over $150,000 for Mr. Yan’s family. “This is a man who we trusted for so many years.”
She added: “This was a family who was trying to live the American dream. It’s devastating.”
Since her husband’s death, Ms. Zhao has focused on helping the couple’s children cope with the loss of their father, said Jennifer Wu, a lawyer who is representing the family.
One of Ms. Zhao’s most pressing concerns has been how to invest the money friends and strangers have donated. She wants to use the money to help fund her 2-year-old daughter’s education, Ms. Wu said.
“It was just heartbreaking to hear,” Ms. Wu said. “Instead of worrying about herself, she just wanted to give everything she had to her daughter.”