The terrifying spate of arson fires in Los Angeles may have been triggered by an unpaid bill for a boob job.

Prosecutors believe 24-year-old Harry Burkhart's anger over his mother's arrest for not paying for allegedly her breast implants led him to set the fires.

His 53-year-old mother, Dorothee, was arrested by U.S. Marshals last week. Court papers say she is a fugitive from Germany charged with embezzlement and fraud, including failure to pay $10,000 for breast augmentation surgery.

There was an emotional outburst when she appeared in federal court Tuesday.

Tom Mroznek of the Justice Department told reporters, "Miss Burkhart addressed the gallery and addressed the judge, saying essentially, 'Where's my son? What happened to my son? I haven't heard from him since yesterday.' The indication I got from that is she does not know that her son has been taken into custody."

The German media is dubbing Harry Burkhart the Hollywood Fire Devil.

And in a startling development, INSIDE EDITION has learned that Burkhart is also under inverstigation in Germany for setting fire to a house in his hometown.