The FBI said Tuesday that it has removed a contractor in charge of its job portal because an internal investigation into a hack last month revealed that a “security failure” by the contractor likely caused the breach.

The cyber-extortion group ShinyHunters has claimed credit for last month's hack of the bureau's fbijobs.gov portal, according to NBC News. The group said it used the portal to gain access to other agency programs and told the outlet that it has stolen between two and three terabytes of files.

The FBI said in its statement that it is investigating the group. One person tied to the group was arrested last month.

“To date, our review has determined that the incident occurred as the result of a security failure of a platform managed by a third-party organization — after a contractor failed to implement a security patch explicitly issued to secure the platform,” Cyber Division Assistant Director Brett Leatherman said in a statement.

Leatherman said the bureau has "taken all necessary steps to both mitigate any further risk and protect our workforce," and his team "will continue to bring the responsible parties to justice, with multiple arrests already occurring.”

The FBI has not identified the contractor, but said it is still "aggressively" investigating the case and "the cyber-criminal group ShinyHunters with all available resources."

Misty Severi is a news reporter for Just The News. You can follow her on X for more coverage.