A law has come into effect in Russia allowing the authorities to blacklist websites seen as offering content that is harmful to children.The controversial law gives officials the right to force websites offline and demand that Internet service providers block content it deems offensive.The Russian government says the law is aimed at protecting children from pornography and web content that encourages drug use or suicide.But free-speech advocates say the new law may be used to block websites seen as critical of the government or the Russian state.The Russian search engine Yandex and the networking site Mail.ru have protested the law, saying it will lead to widespread Internet censorship.A list of websites included on the blacklist can be found at