The HBO hack may have been worse than the initial leaks of a few unaired TV show episodes suggested. A security company hired by HBO to scrub search results for the hacked files from search engines has told Google that the hackers stole “thousands of Home Box Office (HBO) internal company documents.”

The disclosure came as part of a DMCA take-down notice sent to Google Tuesday to force the search engine to take down links to the leaked files. The take-down notice also detailed that the hackers did away with “masses of copyrighted items including documents, images, videos and sound.”

The company in question, IP Echelon, is frequently being used by HBO to remove links to infringing material from Google. An HBO spokesperson declined to comment on the take-down notice and the nature of any files stolen by the hackers when contacted by Variety Wednesday “due to an ongoing investigation.”

Word of HBO getting hacked first broke Monday morning, when the hackers approached media outlets with the news that they had broken into HBO’s networks and released episodes of “Ballers,” “Insecure,” and “Room 104” as well as the script for an upcoming episode of “Game of Thrones.”

Also released by the hackers: Two episodes of “Barry,” the hit man comedy starring Bill Hader that is not scheduled to air until 2018 on the network.

The hackers appear to have also leaked personal information of a senior HBO executive. That information, published online in a text document, contains access information to dozens of online accounts, including paid newspaper subscriptions, online banking, and personal health services. At least one of these accounts may also have given the hackers access to the executive’s work email.

The perpetrators of the hack have claimed that they were able to access some of HBO’s key network infrastructure, and steal a total of 1.5 terabyte of data, and have suggested that they will release additional information in the near future. An image file published as part of the leaks seems to corroborate at least the first part of that claim, as it appears to show screenshots of HBO’s internal administration tools, listing employee names and email addresses and their functions within the organization.

Thousands of potentially sensitive internal documents, employee data, and a possible access to internal corporate email: All of this brings back memories of the Sony hack. Back in 2014, a group of hackers that is thought to have been backed by North Korea broke into the networks of Sony Pictures. The group subsequently released tens of thousands of emails, as well as scripts and video files, contributing to the ouster of Sony Pictures chief Amy Pascal.

HBO acknowledged the hack on Monday, and said that it was working with law enforcement and private firms to remedy the situation. “Data protection is a top priority at HBO, and we take seriously our responsibility to protect the data we hold,” the company said in a statement.