KeyPoint Government Solutions, which took over the bulk of federal background checks after one of its competitors was hacked, also recently suffered a computer network breach, officials said Thursday.

While there was “no conclusive evidence to confirm sensitive information was removed from the system,” Office of Personnel Management spokeswoman Nathaly Arriola said the agency would notify 48,439 federal workers that their personal information may have been exposed.

The breach comes just a few months after OPM decided not to renew a background investigations contract with USIS, which suffered a breach earlier this year.

USIS had been the largest provider of background checks used in security clearances for the federal government for years. After OPM decided not to renew USIS’s contract, Colorado-based KeyPoint quickly picked up the bulk of the work for the federal government.

KeyPoint and USIS declined to comment.

Earlier this month, USIS pushed back against criticism that it didn’t do enough to prevent a massive cyberattack and accused the OPM of neglecting to share information that might have helped it detect the intrusion earlier.

USIS, based in Falls Church, Va., said it sought to work closely with OPM after the breach. But the company wrote that “no meaningful partnership will ever exist if the U.S. government response to cooperation is to punish and shut down organizations that, like so many government agencies, happen to fall victim to a cyber attack.”

KeyPoint’s breach was yet another in a series of problems that have plagued the background-check process. Before it was hacked, USIS was accused in a whistleblower lawsuit, joined by the Justice Department, of “flushing” hundreds of thousands of checks — meaning they were submitted as complete even though they were not.

And members of Congress repeatedly urged OPM to end its contract with USIS.

The termination of the contracts on Sept. 30 had a devastating effect on USIS, which at one point employed about 3,000 workers in its investigations division.

KeyPoint moved quickly to fill the void, looking to double the size of its investigative workforce.

But USIS’s caseload was significant — 21,000 background checks a month, and once its contract was not renewed, some wondered who would be able to handle the task on short notice.

That amount of work requires significant managerial oversight, which is usually developed over time, said Nicole Smith, a former USIS senior investigator who now is an attorney at Tully Rinckey working on security clearance issues.

Once KeyPoint took over, she said one of the questions that concerned her was: “Can they even handle the influx of these new employees and all the work that gets dumped on them from OPM?”

In an e-mail to OPM colleagues, Donna Seymour, the agency’s chief information officer, said that “following the discovery of the problem, KeyPoint implemented numerous controls to strengthen the security of its network. The immediacy with which KeyPoint was able to remediate vulnerabilities has allowed us to continue to conduct business with the company without interruption.”

In the e-mail, a copy of which was obtained by The Washington Post, she said that the “security of our network and the data entrusted to us remains our top priority. This incident serves as yet another reminder that we all must be ever-vigilant in our efforts to understand, anticipate and guard against the threat of cyber-attacks.”

Arriola, the OPM spokeswoman, declined to comment on the sophistication of the attack or who might have been behind it, saying the investigation was ongoing. OPM will offer the employees free credit monitoring.