The Human Rights Campaign (HRC), the nation's largest LGBT rights advocate, has denounced the passage of a constitutional amendment in Russia that defines marriage as a heterosexual union.

Russian voters approved more than 200 constitutional amendments during a recent referendum that lasted seven days. Voters also approved an amendment that paves the way for Russian President Vladimir Putin to remain in power until 2036.

More than two-thirds of voters approved the proposals.

In a statement, HRC President Alphonso David said that Russia is “tripling down” on its attacks against the LGBT community.

“Russia is tripling down on its attacks on the basic human rights and dignity of LGBTQ people by adding constitutional prohibitions against marriage equality,” David said. “Putin and his administration used propaganda brochures leading up to the election promising a return to ‘traditional family values,’ using marriage between loving couples as a wedge to push through his nefarious agenda. It is shameful, manipulative and malicious. Any leader who would resort to scapegoating LGBTQ people for political gain is a threat to the human rights of all.”

In 2013, Russia approved a law that prohibits “gay propaganda.” Putin has said that the law is needed to protect children. The law prohibits positive portrayals of the LGBT community and has been used to silence LGBT activists.

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The Russian LGBTQ Network also responded to the vote.

“The main purpose of adopting [a] series of amendments to the constitution is to keep in power [the] current government and Russian President,” the group said. “We consider other constitutional changes artificial to gain people's attention.”