Panicked 911 calls from an Allen, Texas, outlet mall captured moments of chaos and terror as the nation's second-deadliest mass shooting so far this year unfolded, with eight killed and others wounded within minutes.

As gunfire erupted on May 6, calls poured in from distraught shoppers, some crying into their phones pleading for help and describing wounded loved ones, and others searching for guidance as they hid from the gunman, according 911 audio obtained by CNN affiliate WFAA.

"Stay safe and stay down," "take cover" and "keep your head down," are some of the phrases that audibly overwhelmed operators are heard telling anxious callers as phones ring in the background.

"Are you injured?" the operators ask, call after call.

A gunman dressed in tactical gear and armed with an AR-15-style weapon was moving through Allen Premium Outlets, having first fired shots in the mall's parking lot near an H&M store, witnesses and authorities said.

Operators directed some callers to try to stop victims' bleeding or stay hidden and wait for police if they weren't with anyone wounded. "I'm sorry, I gotta let you go," was the kind of thing they often told callers before answering other distressing pleas for help.

Stores that are American mall staples became callers' markers for where gunshot victims are located and where the shooter was last seen.

"Hello, I have a shooting victim," one caller begins, reporting a victim shot in the stomach at or near an H&M store.

"Keep her safe, please. Can you please press something on it to stop the bleeding?" an operator instructs the caller, before saying that help was on the way.

Sightings of the gunman also begin rolling in: One caller reports he was seen at a beauty products store and that the gunman just shot a security guard. Another says the shooter was walking outside a watches and accessories shop; another reports him outside a clothing store.

The calls also detail confusion that exploded across the mall.

One caller reports a gunshot victim at a clothing boutique. "I think it's in his chest," the caller says when asked to describe the wound.

"Are you with the guy that was shot?" an operator asks.

"No, I left him in there because I wasn't sure if he was a shooter," the caller responds.

Another person calls to say someone who was shot at, but not wounded, appears to be having a heart attack.

The massacre ended when an Allen officer, who was at the scene for an unrelated call, shot and killed the gunman, police said.

Paramedics found a gruesome scene, with some victims riddled with gunshot wounds and people drenched in blood, witnesses have described.

Killed were Cho Kyu Song, 37, his wife, Kang Shin Young, 35, and their 3-year-old son James; elementary school students and sisters Daniela and Sofia Mendoza; 20-year-old mall security guard Christian LaCour; Aishwarya Thatikonda; and Elio Cumana-Rivas, 32.

At least seven others were also wounded in the shooting, which marked at least the 202nd mass shooting the US had suffered at that point in the year, according to the Gun Violence Archive. The nonprofit and CNN define mass shootings as those in which four or more people are shot, excluding the shooter.

The number for 2023 has since risen to at least 225, according to the archive.

Gunman had social media posts on Nazism and mass shootings

The gunman, 33-year-old Mauricio Garcia, left behind online posts in which he appears to have espoused support for Nazism and obsessed over guns and prior mass shootings.

After he was shot, Garcia was found wearing a patch that reads "RWDS," which authorities believe may stand for "Right Wing Death Squad," a senior law enforcement source familiar with the investigation told CNN.

The insignia also appears to be shown in a photo posted by an account user on the Russian social media website Odnoklassniki that a law enforcement source said investigators believe belongs to Garcia.

In the weeks leading up to the mall massacre, the user posted a screenshot from Google Maps showing what times of day the mall was busiest. The user also posted a photo of the mall and writings supporting Nazi ideology.

Several activist groups in North Texas are calling for local and federal authorities to determine if the shooting was a hate crime.

"We are demanding a full and thorough investigation by local and federal officials to determine if this was a racially motivated hate crime, timely and accurate information from the Department of Public Safety and local law enforcement, and swift action on gun safety reform at all levels," said Stephanie Drenka, co-founder and executive director of the Dallas Asian American Historical Society.

No motive has been announced in the shooting, but officials have said it did not appear the gunman was targeting people based on their ethnicity during the attack.

"To me, it looks like he targeted a location rather than a specific group of people," Texas Department of Public Safety Regional Director Hank Sibley said.