JACKSON, Miss. — Hundreds of supporters of lesbian, gay bisexual and transgender rights protested Sunday against a new Mississippi law they call discriminatory, saying they’re not giving up their fight.

The law, which takes effect July 1, is to allow religious groups and some private businesses to deny services to same-sex couples and transgender people.

More than 300 people marched from the state Capitol to the governor’s mansion in Jackson, the capital city, bidding to keep up pressure on Gov. Phil Bryant and other Mississippi leaders who support the law.

“We need to show him loud and clear we’re not going away,” Chad Griffin, president of the Human Rights Campaign, told the crowd gathered outside the white columned-mansion.

The only signs of activity inside the mansion’s wrought iron fence were a few State Capitol police officers walking around.

Bryant and other supporters have said the law reinforces the First Amendment guarantee of freedom of religion. They also said opponents are overreacting, and that Mississippi needed to take action after the Supreme Court legalized gay marriage.

The law would allow a church group to decline services including housing or adoption to gay couples. Private businesses could refuse marriage-related services such as room rentals, cakes, photography or flowers. Any employer or school could refuse to allow a transgender person to use the bathroom of their choice.