In an attempt to "right a wrong," Thelmas said, school staff and parents led the singers outside the store, where they gathered under a nearby flag that was at half-staff. The children performed "God Bless America." The group had headed to its cars when police showed up in response to a report of a "flash mob situation."
Wednesday evening, responding to complaints about the incident, a Walmart spokeswoman apologized.
"We regret this happened and apologize to the students, parents, and the school for this experience," said the spokeswoman, Kayla Whaling, based in Bentonville, Ark. "Unfortunately, this was a situation of miscommunication, and it should have been handled differently."
She added, "We're also inviting the kids back to the store to help honor the victims and fallen heroes."
The performance at Walmart had been arranged as part of a school-related "I Will" campaign, which encourages people to help a stranger and do a public service on 9/11.
Music instructor Annie Conner and the students envisioned a "flash mob" performance at Walmart, Thelmas said. In addition to remembering the victims, the act was meant to surprise and cheer up customers, Thelmas said.
Thelmas said that when she contacted the store last week, she was referred to a manager named Frank, who approved the in-store performance. But when the group showed up Tuesday night, Frank wasn't there, Thelmas said. Instead, another Walmart manager dismissed the idea, called the chorus "a liability" and turned the group away, Thelmas said. The employee added that Frank had been "fired," Thelmas said.
Walmart declined to discuss details.