CHARLOTTE, N.C. (AP) – The NAACP and others are pressing ahead with a lawsuit after Governor Pat McCrory quietly signed into law a Republican-supported measure that makes sweeping changes in how and when North Carolina residents can cast their ballots.

Within hours of Monday’s signing, the American Civil Liberties Union announced that it and two other groups had filed a lawsuit challenging the legislation.

There was no formal ceremony marking the bill signing. Gov. McCrory’s press office sent out a statement saying he signed the legislation, and also posted a 95-second message on YouTube giving his reasons. It would take effect in 2016.

Republicans have said the legislation is meant to prevent voter fraud, which they claim is both rampant and undetected. But non-partisan voting rights groups, Democrats and libertarians suggested the true goal is to suppress voter turnout, especially among blacks, the young, the elderly and the poor.