A U.S. law firm is accusing singer Lady Gaga of scamming her own charity for Japanese earthquake victims just days after the colorful pop star headlined an MTV charity concert near Tokyo.

The American lawyers, who advertise on television using the telephone number 1-800-LAWFIRM, take aim in their lawsuit at Lady Gaga's Internet sale of $5 “Pray for Japan” bracelets of her own design. They say she inflated the $4 shipping costs and has been pocketing part of the proceeds.

The lawyers have filed a $5 million suit under a law aimed at prosecuting racketeers, removing some of the glow from Saturday night's highly successful benefit concert in Japan. The concert was sponsored by MTV, which arranged the event to raise money for earthquake victims in place of its annual awards show.

Lady Gaga performed the title track from her latest album, “Born This Way,” in a show that also featured top Asian pop groups. Among them were Japanese girl group AKB48 and South Korean group Girls Generation.