There were so many gun sales in Pennsylvania last month that it caused the online state background check system to crash.

That was one of the first signs of a spike, along with long lines at gun shops and a run on ammo, according to the Pennsylvania State Police.

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Data released Tuesday confirmed what they were expecting.

"It’s clear the volume went up as COVID-19 awareness grew in mid-to-late March," said Ryan Tarkowski, communications director for the Pennsylvania State Police.

There were 304,876 background checks conducted in Pennsylvania during the first quarter of 2020, up 14 percent from 266,442 during the same quarter in 2019.

The highest number of background checks came on March 20, when the system scanned 8,346 buyers. Pennsylvania hadn't run that many checks since Black Friday, Nov. 24, 2017, when 9,178 checks were conducted, Tarkowski said.

The other busiest days of the quarter were in the same month: 7,704 checks on March 16 and 7,313 checks on March 19.

Those peak days occurred the same week President Donald Trump declared a national emergency and signed into law a coronavirus relief package and Gov. Tom Wolf closed all Pennsylvania schools for at least two weeks.

Wolf ordered a shutdown of all non-essential businesses on March 19, and that day and the following day were two of the three busiest days for firearm purchases in Pennsylvania.

State police data also shows 4,866 people were denied firearm purchases after their background checks. More than 1,200 of those denials were referred to law enforcement agencies, and 59 people were arrested at the point of purchase.

Though denials were up 1,606 year-over-year, Tarkowski said it was a normal, proportional increase.

"When background checks are up, it makes sense that denials are also up," he said.

There were rumors, Tarkowski said, that the state background check system wasn't operating.

"We want people to know that's not true. We're still running background checks. We're still open," he said.

The Pennsylvania Instant Check System, as it's formally known, is used by licensed firearms dealers, county sheriffs and police chiefs in first-class cities to determine a person's legal ability to acquire a firearm through a purchase or transfer.

State police do not have a county-by-county breakdown of background checks and denials, and Tarkowski said he couldn't say specifically why most people were denied.

Investigations are triggered if someone provides false information during a background check, according to state police.

"In Pennsylvania, a person commits a felony of the third degree if they make a false oral or written statement on any federal or state agency form or willfully presents false identification that is likely to deceive a firearm seller, licensed dealer or licensed manufacturer," state police said in a news release.

During background checks, people may also be identified as having an active warrant for their arrest.

State police will release their next tally of quarterly background checks and denials in early July.

Candy Woodall is a reporter for the USA Today Network. She can be reached at 717-480-1783 or on Twitter at @candynotcandace.

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