Hackers have released a trove of internal documents from the Washington, D.C., police in what experts say is the worst such ransomware attack in the U.S. The cybergang, known as Babuk, reportedly released the sensitive materials on the dark web after a failed blackmail attempt. The information includes officers’ personal data, psychological evaluations and disciplinary records. Some documents also involve intelligence agencies and relate to the January 6 insurrection and the presidential inauguration.

This comes a week after another ransomware attack shut down the Colonial Pipeline’s fuel supply, triggering shortages and sending gas prices soaring. Media are reporting Colonial Pipeline paid nearly $5 million in ransom to the hackers in order to restore its disabled computer network. President Biden said Thursday those behind that attack are likely based in Russia but not believed to be linked to the Russian government.