Gunfire rang out Monday afternoon in a home in Broken Arrow, an Oklahoma city 15 miles southeast of Tulsa. Three intruders were killed after the son of the homeowner fired a semiautomatic rifle in what local law enforcement officers later described as an act of self-defense, though their investigation remains open.

The intruders — a 16-year-old, a 17-year-old and a man thought to be 18 or 19 — had smashed open the back door of the house, the Wagoner County Sheriff’s Office said in a statement posted to Facebook. Their plan was burglary, authorities said.

They wore gloves, masks and all-black clothes, Wagoner County Deputy Nick Mahoney told Tulsa World. Two of the teenagers were armed, one with a knife and the other with brass knuckles.

The trio reportedly exchanged words with the 23-year-old son of the homeowner, whose name has also not been released. He fired on them with an AR-15, a popular semiautomatic rifle, officials told Fox 23.

The shots seemed to shatter the day like a thunderstorm, one neighbor told CBS affiliate KOTV-TV.

“Upon making entry to the home one of the residents fired a rifle striking all three of the suspects,” the sheriff’s office statement said.

Two of the intruders died inside the kitchen. The other “was able to run to the driveway before succumbing to his injuries,” the statement said.

The homeowner and his son gave formal statements at the sheriff’s office.

Authorities later said the suspected getaway driver, Elizabeth Rodriguez, turned herself in at the Broken Arrow Police Department, the Tulsa World reported. The 21-year-old was arrested on complaints of first degree murder, three counts, as well as three counts of burglary. “A person who is committing a felony when a death occurs can be charged with felony murder,” Tulsa World explained.

Several nearby homes had been burglarized in recent weeks, neighbor Leon Simmons told KOTV-TV. Authorities said they could not speculate as to whether this incident was related to the others.

The sheriff’s deputy described the shooting as an abnormal occurrence in the typically quiet Wagoner County. “This is very, very unusual for us. It’s not something we’re used to,” he told Tulsa World. “It’s not something we normally have.”

Correction: A previous version of this article incorrectly stated that the 21-year-old had been charged with three counts of murder and burglary. She was arrested on complaints of those counts but has not yet been charged.

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