The suspect in a string of arsons in the Los Angeles area is also under investigation in his home country of Germany for a house fire last fall, a prosecutor said Wednesday.

Harry Burkhart, 24, is suspected of setting more than 50 arson attacks over New Year's weekend that caused an estimated $3 million in damage. Authorities believe he was angry over his mother's legal troubles and went on a nighttime rampage of burning parked cars a day after she made an initial court appearance last week. Charges could be filed against him as early as Wednesday.

Burkhart is being investigated in connection with an Oct. 14 house fire in the Marburg area north of Frankfurt, Germany, Marburg prosecutors' spokeswoman Annemarie Wied told The Associated Press on Wednesday. He came to authorities' attention after filing an insurance claim on the house owned by his family on the day it burned down, she said.

Burkhart has not yet been questioned in the case, and there has been no warrant issued for his arrest, Wied said.

Court documents unsealed Tuesday revealed that Burkhart's mother, Dorothee Burkhart, is charged in Germany with 19 counts of fraud, including failing to pay for a 2004 breast augmentation surgery and pilfering security deposits from renters.

During a federal court appearance Tuesday in Los Angeles, Dorothee Burkhart scanned the room looking for her son, apparently unaware he was also behind bars.

"Can you bring my son inside?" she pleaded with court officials. "Where is my son?"

She appeared perplexed, wondering aloud if her son had disappeared or was dead. At one point, she said he is mentally ill and questioned whether Nazis knew where she and her son lived.

Both mother and son are being held without bail. Her next court hearing was delayed until Friday so she can hire an attorney.

Harry Burkhart was taken into custody after authorities received a tip from federal officials who recognized him in a security video that showed a ponytailed 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.

Burkhart had been in court Thursday afternoon at his mother's hearing when he launched into an obscenity-laden tirade, saying "F--- the United States!" said Thom Mrozek, spokesman at the U.S. attorney's office in Los Angeles.

Mrozek said Burkhart was detained and later escorted out of the courthouse. He said Burkhart did not make any specific threats.

A law enforcement official, who requested anonymity because the investigation is ongoing, said authorities believe Burkhart went on the arson spree because he was angry over his mother's legal troubles.

Burkhart arrived in the U.S. in October, and his nonimmigrant visa is set to expire Jan. 18, authorities said. His mother last entered the country lawfully in January 2007 and she left four months later, officials said.

In May 2010, Burkhart and his mother applied for refugee status in Canada but were denied. The Immigration and Refugee Board determined in November 2009 Burkhart was "not a person in need of protection."

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.

Outside Burkhart's Hollywood apartment, some neighbours 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.

"He loved his mom, the way every son loves his mom," Elady said. "He's not a creepy guy."

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.

The fires forced many apartment dwellers from their homes. There were no serious injuries.