Animal rights theorist Tom Regan dies

American philosopher and prominent animal rights theorist Tom Regan has died, US media reported on Sunday. He was 78.

Professor emeritus of philosophy at the University of North Carolina, he wrote "The Case for Animal Rights," a 1983 book that proved seminal for the movement.

Regan argued that if people value humans for more than their ability to be rational actors, they must also value non-human life.

A spokesman for the family was reported as saying that Regan died Friday in North Carolina after battling pneumonia.

According to his website, he was born on November 28, 1938. It gave the date of his death as February 17, 2017.

Another animal rights theorist, Peter Singer, professor of bioethics at Princeton University, tweeted on Friday: "I've just heard that sad news that Tom Regan, a philosophical pioneer for animals who I have known since 1973, died this morning."

In France, the Brigitte Bardot Foundation, which supports animal rights, called Regan the "principal theorist of animal rights."

"His analysis is the most impressive and thorough ever produced," the foundation wrote on Twitter.

Regan's site prominently features his most famous speech, delivered in 1988, appealing to researchers working with animals not to conduct vivisections.

"Lay down these weapons of evil and join with us, you scientists who are brave enough and good enough to stand for what is just and true," he said.