Authorities have yet to disclose why they believe that the pony-tailed, 24-year-old Hollywood resident set the fires, but his mother's legal trouble provides one glimpse into the turmoil in his life.
Court documents unsealed Tuesday said Dorothee Burkhart, who is in her 50s, was charged with 19 counts of fraud in Frankfurt, including failing to pay for a 2004 breast-augmentation surgery and pilfering security deposits from renters.
In a brief court appearance, she appeared perplexed, wondering aloud if her son was dead.
At one point, she said, he is mentally ill.
"Where is my son? What did you do to my son?" she asked U.S. Magistrate Judge Margaret Nagle.
Harry Burkhart was being held without bail after being arrested in the arson case Monday.
Outside his Hollywood apartment, some neighbors described him as a loner who loitered around the busy commercial strip at night and could be heard arguing with his mother.
But Shlomo Elady, a hair stylist who regularly trimmed Burkhart's long hair, recalled someone who spoke three languages, dreamed of visiting Jerusalem and cared for a sickly mother who had trouble walking.
Elady said he was stunned that the man who lived with his mother above his Sunset Boulevard shop is suspected of torching vehicles, some just steps from his home. The fires caused an estimated $3 million in damage.
"He loved his mom, the way every son loves his mom," Elady said. "He's not a creepy guy."
Burkhart was taken into custody after authorities received a tip from federal officials who recognized him in a security video that showed a pony-tailed man emerging from a garage where a car was set ablaze.
"When they saw the security footage, they recognized him and they contacted the arson task force," a State Department official told The Associated Press, speaking on condition of anonymity because the investigations are ongoing.
The official didn't know her status or what type of visas the pair used to enter the country. As German citizens, they would be eligible to come to the U.S. without a visa for 90 days under the Visa Waiver Program.
A federal law enforcement official, speaking on condition of anonymity because the official was not authorized to discuss the case, said Harry Burkhart was present when his mother was arrested Dec. 28 on a provisional arrest warrant.
Provisional arrest warrants are normally issued when there are criminal charges pending overseas against someone. Ordinarily, U.S. authorities then obtain an arrest warrant through the State Department and the Justice Department.
Burkhart had been in court Thursday afternoon. During that hearing, a man had an outburst and was escorted out of the courtroom by authorities, Mrozek said. He could not immediately verify the identity of the man or what he said.
Galina Illarionova, who lives in the same apartment complex as the suspect, said through a Russian translator that an agitated Burkhart visited her Sunday and said his mother was having some kind of legal problems.
He told her his mother was in trouble with authorities and wanted Illarionova to attend a legal hearing with him, but he later said he didn't need her help.
A domain name for a website offering appointment-only sensual massage is registered to Dorothee Burkhart. Her name is not mentioned on the website, which states the service is not prostitution.
The series of fires appeared to have stopped with Burkhart's arrest. The onslaught of intentionally set fires kept residents anxious over the holiday weekend in some of the most densely populated areas of the city.
One of Saturday's fires occurred at the Hollywood and Highland entertainment complex, a popular tourist destination bordered by the Walk of Fame in a neighborhood that includes Grauman's Chinese Theatre.
Damaged buildings included a former home of Doors singer Jim Morrison.
Hundreds of investigators, police officers and firefighters raced to deal with the blazes. Police conducted extra patrols all weekend, and the noise of helicopters and sirens persisted virtually nonstop in Hollywood.
The fires forced many apartment dwellers from their homes. There were no serious injuries.
Associated Press writers Greg Risling in Los Angeles and Pete Yost in Washington, D.C. contributed to this report.