The Federal Bureau of Investigation officials have been scrambling to check the damage from a possibly devastating breach across several U.S. government computer networks.

The country's cybersecurity agency on Thursday released an alert saying that the breach posed a huge risk of the U.S. government, as reported by ABC News.

This includes the State, Commerce, and Treasury departments. Local, tribal, and territorial governments and other private sector organizations were also involved.

FBI released a statement on Wednesday night, saying that it is investigating the said breach. However, officials have said little else about the damage.

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Biden pledges to improve cybersecurity

U.S. President Donald Trump has yet to comment on the attack, which officials believed is to be connected to Russia.

Meanwhile, President-elect Joe Biden released a statement on Thursday, describing the situation as a matter of great concern.

"I have instructed my team to learn as much as we can about this breach, and Vice President-elect Harris and I are grateful to the career public servants who have briefed our team on their findings, and who are working around-the-clock to respond to this attack," Biden was quoted on Bloomberg.

The president-elect added that they will improve cybersecurity as an imperative across government.

Biden added that they will also further strengthen partnerships with the private sector, as well as expanding the country's investment in infrastructure and people the nation needs to defend the government from cyberattacks.

However, he noted that defense is not enough and they need to disrupt and deter adversaries from undertaking significant cyber-attacks.

Biden said that the country's adversaries should know that as president of the United States, he will not stand idly by in the face of cyber assaults.

He also added that they will be imposing substantial costs on those responsible for such attacks, and will be coordinating with allies and partners

The statement is Biden's first formal response as president-elect of the United States.

CNBC reported that it signals a possible change to tougher stance against Russian cyber-warfare tactics as compared to the current Trump administration.

Biden also said that his incoming national team has been briefed on the attacks by career officials at relevant government agencies.

The FBI, the Cybersecurity and Infrastructure Security Agency, or CISA, and the Office of the Director of National Intelligence announced the creation of a joint command respond to what they described as an ongoing cybersecurity campaign against the U.S.

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Russians suspected behind the cyber attack

CISA did not identify who was behind the attack, which agencies and organizations had been breached, and what information had been stolen or exposed, according to a BBC news report. But some are claiming that Russians may be behind the attack.

Government agencies and private-sector companies targeted were fast-tracking the development of a clearer picture of the full extent of the breach, as well as the possible damage to U.S.

Meanwhile, White House spokeswoman Kayleigh McEnany said on Tuesday that the current administration is taking a hard look on the matter.

Utah Sen. Mitt Romney, Republican, calls the White House response to the attack as inexcusable.