RALEIGH — A protest led by the North Carolina NAACP started in April with dozens of supporters and 18 arrests. Now it has grown to nearly 1,000 supporters with more than 80 arrested at the state legislature.

The civil rights group has organized near-weekly demonstrations railing against the health and environmental policies of the legislature.

The near-weekly protests have grown to encompass a wider coalition of left-leaning demonstrators who are outraged over Republican policies ranging from social spending to education and voting rights. Monday’s protests brought the arrest total to more than 450 as NAACP chapter president the Rev. William Barber called for mass rallies for the next two weeks of demonstrations.

Republicans control both chambers of the General Assembly and the executive branch simultaneously for the first time since 1870.

Supporters varying in age and ethnicity held signs emphasizing that they are locals in response to comments from Gov. Pat McCrory and the state Republican Party chairman that protesters represent outside interests.

“We don’t need any outside support to get this point across,” said Marge Macintyre of Chapel Hill.

Others held up signs opposing legislation that critics fear will speed up oil and gas drilling in the state. Many critics say hydraulic fracturing, known as “fracking,” poses threats to water supplies.

“The technology of fracking is not ready for primetime,” said Ken Crossen, who said he’s an engineer from Pittsboro. “This whole thing is political, but it ought to be driven by engineering.”

Outside the Senate chambers — where protesters have gathered each week to deliver speeches, chants and songs — supporters drowned out initial commands to disperse issued through megaphone by General Assembly Police Chief Jeff Weaver. Barber tried to quiet the crowd to let individual speakers explain why they were choosing to be arrested.

“If you want justice, you have to let people say why we’re here,” he said.

The legislature is expected to wrap up its regular yearly session in the coming weeks.

Barber said that the NAACP will continue leading events that bring greater attention to the policies of the legislature even after it adjourns.

“This is not a temporary exercise in futility,” he said. “This is a movement.”