COLORADO, USA — The Florida woman accused of making a "credible threat" that prompted the closure of more than 1,000 Colorado schools legally purchased a gun at a store near Columbine High School the day before she was found dead, according to the FBI.

Sol Pais, 18, purchased the gun at Colorado Gun Broker, a gun store at 8966 W. Bowles Ave. in unincorporated Jefferson County on Monday, 9Wants to Know confirmed with a store spokesperson. The store is about 2 miles west of the school.

Pais was found dead from a self-inflicted gunshot wound Wednesday morning.

RELATED: Search for Sol Pais is over: The Florida woman was found dead from a self-inflicted gunshot wound

Colorado Gun Broker spokesperson Josh Rayburn said the Pais underwent a full background check and was cleared by both the National Instant Criminal Background Check System (NCIS) and the Colorado Bureau of Investigation (CBI). 

"We had no reason to suspect she was a threat to either herself or anyone else," Rayburn said. "We are very sorry to hear of the outcome in this situation. It is never good when someone loses their life."

"We are praying for her family — and are very thankful this situation did not escalate into a public tragedy," he added.

While Pais' background check came back clean, some have pointed out that perhaps she still shouldn't have been allowed to buy a gun. Federal code states a sale of a firearm is legal "provided the transaction complies with state law in the state where the licensee is located and in the state where the purchaser resides."

In this case, Pais could legally purchase a shotgun at 18 under Colorado law, but she would have to be 21 to buy the same gun in Florida.

Still, CBI told 9NEWS on Wednesday that "as of now, there is no indication of any unlawful transaction," and the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) said the way the Florida law is written applies only when the buyer is in Florida.

Others have asked 9NEWS if Colorado's new red flag gun control law, signed earlier this month, would apply in this case. The law is formally known as the extreme risk protection order, and it doesn't go into effect until 2020.

Florida adopted a similar red flag law of its own last year, after a shooter killed 17 students at a school in Parkland.

House Majority Leader Alec Garnett (D-Denver), the state legislator who wrote Colorado's version, says that in both states, an active red flag order from a judge to seize someone's guns would show up immediately in a background check. However, "a petition for an extreme risk protection order must be filed in the county where the respondent resides," the law says, meaning the petition would have to be filed in Florida.

If a red flag order has expired in Florida, or in Colorado next year when the law takes effect, it's scrubbed from the national background check system and wouldn't stop a gun sale.

When the gun shop in Jefferson County ran its check, it appears there was no such active red flag order against the woman. During a news conference Wednesday, the FBI said Pais bought the firearm before the agency considered her a threat.

RELATED: 'It's like a bad dream': Father of Sol Pais says he last saw daughter Sunday

The FBI on Tuesday issued an alert to local agencies saying Pais was considered "armed and dangerous" and had an infatuation with Columbine.

The Denver FBI office then started assessing the threat and determined it was credible.  

That prompted school districts across the state to close Wednesday.

RELATED: Hundreds of schools across Denver-area closed during search for Sol Pais; She has been found

9NEWS received multiple other inquiries about the legalities of purchasing a gun in Colorado.

Below are frequently asked questions — and answers — regarding Colorado gun law, according to the National Rifle Association and the Giffords Law Center.

How old do you have to be to purchase a rifle or shotgun in Colorado?

18. 

How about a handgun?

21. 

Does a seller have to conduct a background check before the transaction?

Yes. 

Does an individual need a permit to purchase a shotgun, rifle or handgun?

No, there is no state permit required.

Does the background check cost money?

The Colorado Bureau of Investigation charges dealers a fee to cover the costs of operating the background check system. The fee for private dealers is $10.

Do gun dealers keep records of  handgun purchases?

Yes, they are required to keep a record on the retail sale, rental and exchange of handguns.

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