A U.S. Senate candidate is suing the city of Cambridge, saying officials violated his First Amendment rights by demanding he remove a sign from a campaign bus that read: “Only a REAL INDIAN Can Defeat the Fake Indian.”

Shiva Ayyadurai, who was born in India, is running as an independent against Democratic Sen. Elizabeth Warren.

The slogan refers to claims Warren has made about Native American ancestry. It appears with an image of Warren that someone manipulated to show her in a Native American headdress.

Read the full article at the Boston.com website.