The bill by Africa's most populous nation calls for a 14-year sentence for anyone convicted of homosexuality. Anyone who aids or "abets" same-sex unions faces 10 years in prison, a provision that could target rights groups.
It goes to the nation's House of Representatives for a vote before President Goodluck Jonathan can sign it into law.
"It would place a wide range of people at risk of criminal sanctions, including human rights defenders and anyone else -- including friends, families and colleagues -- who stands up for the rights of lesbian, gay, bisexual or transgender people in Nigeria," Amnesty International said in a statement.
In a recent development, it has been discovered that there has been gay churches with growing numbers of dedicated members in around Lagos.
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