Willcom Inc., a struggling telecommunications company, filed Thursday for bankruptcy protection with the Tokyo District Court.

The provider of personal handy-phone system services, a no-frills, low-cost mobile telephone system, hopes to tap a government-backed turnaround body for funds to help turn around its fortunes.

The company is about ¥206 billion in debt, the most for any telecommunications carrier, according to credit research company Tokyo Shoko Research.