Activists have encouraged a boycott of Indiana after the US state enacted a "religious freedom" law, which they say discriminates against gay people. Supporters say the law prevents the state from forcing people to provide services contrary to their religion. Similar bills are being considered across the US as court rulings have made gay marriage legal in more states. Several groups plan to do less business with the state, and celebrities criticised the law on Twitter. The National Collegiate Athletic Association said it was "especially concerned" about how the law would affect its employees and student athletes. Next week, the NCAA will host the finals of its annual basketball tournament in Indianapolis, the state's capital and its largest city. On Friday, Arkansas moved closer to passing a similar "religious freedom" measure.