AUSTIN, Texas – John Perry Barlow, a lyricist for the Grateful Dead and cyber political activist, died at the age of 70, according to a statement from the Electronic Frontier Foundation, also known as the EFF.

There is no information on an exact cause of death, but he was known to have suffered a heart attack in 2015.

Barlow co-founded the EFF, along with digital rights activists John Gilsome and Mitch Kapor, and was known for his legacy of being an advocate for internet freedom.

At the age of 15, Barlow met Grateful Dead founding member Bob Weir. Barlow began co-writing songs with Weir in 1971. Together, Barlow and Weir wrote “Cassidy,” “Mexicali Blues,” “Black-Throated Wind” and several more songs over the years.

In 1996, Barlow published the "Declaration of the Independence of Cyberspace," where he wrote that the internet is: “A world that all may enter without privilege or prejudice accorded by race, economic power, military force, or station of birth. A world where anyone, anywhere may express his or her beliefs, no matter how singular, without fear of being coerced into silence or conformity.”

In its statement, the EFF wrote that "it is no exaggeration to say that major parts of the internet we all know and love today exist and thrive because of Barlow’s vision and leadership. He always saw the internet as a fundamental place of freedom, where voices long silenced can find an audience and people can connect with others regardless of physical distance."

News of Barlow's death sparked an outpouring of emotion on his Facebook page from both musical artists and members of the technology community.

MORE | Read the full Declaration of the Independence of Cyberspace