A citizen group is standing up to discriminatory speech on Twitter, demanding that the social networking service take urgent measures to block hate speech and other abusive communication.

Experts believe specific guidelines are needed to curb discriminatory tweets. Human rights advocates are concerned that unfettered abuse could lead to major nationalist rallies in Japan similar to those recently seen in the United States.

Earlier this month, protesters gathered in front of the Japanese unit of Twitter Inc. in Chuo Ward, Tokyo, demanding that the company step up efforts to immediately remove from the platform hate speech, such as the many examples of offensive posts targeted against people of Korean descent.