The state of Florida failed for more than a year to carry out national background checks on tens of thousands of people applying for concealed-weapons permits because an employee could not log into the system.

The checks, which cover the criminal and mental health history of those wanting to buy a firearm, are aimed at preventing drug addicts or people with a mental illness from carrying guns in public.

The commissioner in charge of the department, Republican Adam Putnam, who is now running for Florida governor, is a staunch supporter of gun owner rights, and his campaign touts his expansion of permits as a major accomplishment.

According to the Tampa Bay Times, an investigation by the Office of Inspector General found that in February 2016 the Florida Department of Agriculture and Consumer Services stopped using results from an FBI crime database called the National Instant Criminal Background Check System (NICS), which looks at whether applicants have a disqualifying history in other states.

The employee in charge of the background checks could not log into the system, the investigator learned.

The problem went unresolved until it was discovered by another worker 13 months later, the newspaper reported, meaning that applications were approved without the required background check for over a year.

During that time, Florida had an unprecedented spike in applications for concealed weapons permits.

Employees interviewed for the report called the NICS checks "extremely important”.

Agriculture commissioner Mr Putnam has made speeding up the issuing of concealed weapons permits a priority since he was elected in 2010, the Tampa Bay Times said.

In 2012, he celebrated the state's one millionth permit, noting the time to process applications fell from 12 weeks to 35 days on his watch. There are now 1.8m concealed weapon permit-holders in Florida.

Last July – a month after investigators found that his office had botched thousands of background checks – Mr Putnam, a National Rifle Association supporter, tweeted that he was a "proud NRA sellout".

"The integrity of our department's licensing program is our highest priority," Aaron Keller, a department spokesman, told the website. "As soon as we learned that one employee failed to review applicants' non-criminal disqualifying information, we immediately terminated the employee, thoroughly reviewed every application potentially impacted, and implemented safeguards to prevent this from happening again."

Mr Putnam said: "A criminal background investigation was completed on every single application."

"Upon discovery of this former employee's negligence in not conducting the further review required on 365 applications, we immediately completed full background checks on those 365 applications, which resulted in 291 revocations," he added.

"The former employee was both deceitful and negligent, and we immediately launched an investigation and implemented safeguards to ensure this never happens again."

Mr Keller added that the NICS database is used for "non-criminal disqualifying offences" and during this time, the state conducted criminal background checks using two other databases, the Florida Crime Information Center database and the National Crime Information Center database.

The report, issued last week and obtained by the Tampa Bay Times, concluded that the employee in charge of background checks, Lisa Wilde, was negligent.

Forty days after the department stopped using the database, Ms Wilde reported to the Florida Department of Law Enforcement that her login to the background check system wasn't working. But the investigation said she didn't follow up after she continued to experience problems.

She told the website that the licensing department was overwhelmed with applications and she was under pressure from supervisors to quickly approve them.

Florida shooting – in pictures Show all 10 1 /10 Florida shooting – in pictures Florida shooting – in pictures Police arrest a suspect in connection with the shooting at the Marjory Stoneman Douglas High School in Parkland, Florida Reuters Florida shooting – in pictures Parents wait for news after reports of a shooting at Marjory Stoneman Douglas High School in Parkland, Florida AP Florida shooting – in pictures Anxious family members wait for news of students AP Photo/Wilfredo Lee Florida shooting – in pictures Students being evacuated from the school AP Florida shooting – in pictures Students being evacuated from the school Getty Florida shooting – in pictures People gather waiting for word from students AP Florida shooting – in pictures Parents waiting for news on their children AP Florida shooting – in pictures People gather at a hotel where students were taken after the shooting Getty Florida shooting – in pictures Florida Governor Rick Scott speaks to the media as he visits Marjory Stoneman Douglas High School following the shooting AFP/Getty Florida shooting – in pictures Dr. Igor Nichiporenko, Medical Director Trauma, left, and Dr. Evan Boyer, Medical Director, Emergency Services, speak about treating victims and the suspect at a press conference outside Broward Health North hospital AP

From July 2016 through June 2017, which covers most of the period when the system wasn't accessed, 268,000 applications were approved and 6,470 were denied.