A federal grand jury is investigating last month's deadly shooting of three first responders in Burnsville, according to an ex-girlfriend of the shooter who said she testified during the secret proceedings this week.

Noemi del Carmen Torres said she was the first of five people called by prosecutors on Tuesday for questioning before the panel. She said she was asked about Shannon Cortez Gooden's history of possessing firearms and whether he would have been able to force her to buy any guns on his behalf.

"No, I don't want any of that because I feel like he was gonna kill me," Torres said in an interview Wednesday, noting that Gooden was abusive toward her. "I feared for my life, and that's what I told them."

Gooden, 38, was legally barred from possessing firearms or ammunition when he used multiple firearms to unleash 100 rounds during an hourslong standoff Feb. 18. Gooden shot and killed officers Paul Elmstrand and Matthew Ruge, both 27, and firefighter-paramedic Adam Finseth, 40, before he fatally shot himself.

Torres said she lived with Gooden from 2006 to 2016 and shared three children with him, each of whom were among the seven children present with Gooden at the time of the shooting. Torres' youngest daughter, age 12, was in the room with Gooden as he turned his gun on himself. Gooden lived at the Burnsville home with another woman with whom he shared multiple children. Officers responded to the home shortly before 2 a.m. on Feb. 18 after receiving reports of a sexual assault.

A conviction in 2008 for second-degree assault in Dakota County prohibited Gooden from possessing firearms or ammunition. In August 2020, Gooden petitioned the court unsuccessfully to regain his right to a gun. He said that he wanted to protect himself and his family, according to court records.

One of the firearms seized by law enforcement was bought illegally in what is commonly called a "straw purchase," according to the owner of the gun shop where the weapon was obtained weeks before the shooting. John McConkey told the Star Tribune last month that an AR-15 lower receiver was picked up by the purchaser at the Modern Sportsman Gun Shop and Range in Burnsville, roughly 6 miles from where Gooden lived. McConkey said at the time that he did not know whether that weapon was fired during the standoff.

"Straw purchasing" is a state and federal crime and occurs when a person legally able to buy a firearm does so on behalf of a prohibited person, and in the process lies on required federal paperwork at the time of the sale.

The Minnesota Bureau of Criminal Apprehension reported seizing several firearms and a large amount of ammunition at the scene of last month's shooting. The BCA also recovered cartridge casings that showed Gooden had fired "more than 100 rifle rounds at law enforcement and first responders," the agency said.

Torres said she received her subpoena last Thursday and testified Tuesday without a lawyer. She said a prosecutor asked about her history with Gooden, whether he would have been able to force her to buy guns for him and whether he still wanted to possess guns despite being barred from doing so.

"I told them, yeah, he still wanted the gun rights. He was very adamant," Torres said, adding that he was abusive toward her. "I told him flat out: No, I don't want guns in the house. You're gonna kill me or I'm gonna kill you. It's gonna be one or the other."

Torres said Gooden would instead carry knives for protection, which she deemed dangerous enough. "I was scared of that, too."

A spokesperson for the U.S. Attorney's Office in Minnesota said the office cannot confirm or deny the activity of a grand jury, a secret process that is required to bring criminal indictments.

Torres said she did not recognize the other four people called to testify on Tuesday.

A message was also left Wednesday seeking comment from McConkey, the gun store owner. He said last month that the AR-15 lower receiver "was purchased from an out of state online retailer and shipped to our shop for transfer" to the buyer. "The purchaser passed the [FBI] background check and took possession of the firearm on January 15th."

McConkey emphasized that his gun shop "had no way of knowing the lower receiver would end up in a convicted felon's/prohibited person's possession. [Gooden] was not there during the transfer process, nor was his name on any of the enclosed documents."

Staff writer Paul Walsh contributed to this report.