Criticized for excluding indies from music service.

The Digital Rights Agency, a digital music distributor of more than 250 independent record labels, has sent a letter to the CEO of wireless operator Sprint, chiding the company for not including independent music in its wireless download music service.

“It’s simply unacceptable that Sprint continues to exclude independent labels from it’s full-track download service,” wrote DRA’s managing director Tuhin Roy. “Not only do independent labels represent 25% of the music sold in the U.S., but they are the engine that keeps the industry vital and growing.”

Sprint’s music store is powered by Groove Mobile, which has licensing agreements with DRA as well as several independent record labels directly. To make these tracks available on the Sprint Music service, however, Sprint must form its own licensing deals with these as well.

Officials at Sprint tell Billboard that it is in the process of doing exactly that, and expects to announce such deals in the near future. The company has existing licensing relationships with several independent labels and distributors for such content as ringtones and ringback tones that it expects to expand into full song downloads soon. The Sprint Music service currently has 320,000 tracks in its library.

Rival Verizon Wireless, meanwhile, launched its VCast Music service with more than 500,000 tracks, including independent music made available through digital distributor The Orchard.