 China's larger internet portals have posted warnings about hate speech towards Japan. Its platform's the first major move since a Chinese woman died this week defending a Japanese mother and child from a knife attack. A Russian music producer has said that the American rapper Kanye West is visiting Moscow, a rare visit by a Western artist. Rumours that he'll play a concert in Russia have not been confirmed. West has lost credibility in sponsorship deals after expressing admiration for Putin.