The websites of the Massachusetts Institute of Technology and the U.S. Department of Justice were knocked offline Sunday evening by hackers paying tribute to Aaron Swartz, the Internet pioneer and activist who killed himself Friday.

A Twitter account affiliated with the hacktivist group Anonymous tweeted at 7:43 p.m. ET Sunday, “by the way. http://mit.edu/ down. # Anonymous # AaronSwartz.”

According to the website DownForEveryoneOrJustMe.com, both MIT.edu and DOJ.gov were completely offline Sunday evening. At press time, only MIT’s site was restored.

Swartz, the 26-year old co-founder of the social media website Reddit, hanged himself in his Brooklyn apartment Friday after battling the Justice Department for more than a year and a half over allegations he illegally downloaded approximately four million scientific documents at MIT’s campus, with the goal of making the information freely and publicly available.

Swartz’s family and partner released an official statement Saturday in which they said they believe the actions of MIT and the federal government contributed to Swartz’s death. Swartz had also battled depression for several years.

The documents Swartz obtained were provided by JSTOR, a private online archiving service for academic research papers that contracted with MIT to provide students and researchers access to the information. Many of the documents contained research funded by taxpayers.

JSTOR dropped charges against Swartz, but the U.S. Attorney’s Office decided to pursue the case. Swartz, who pleaded not guilty, was charged with 13 counts of felony hacking, potentially facing a million-dollar trial in April and 30 years in federal prison.

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