Updated

A California judge set bail at $2.85 million for a German man charged with arson in connection with a series of fires in Los Angeles over the New Year's weekend.

Harry Burkhart, 24, made his first official court appearance Wednesday and was charged with 28 counts of arson of property and nine counts of arson of an inhabited structure, District Attorney Steve Cooley said. Prosecution says more charges are likely as the investigation continues.

Burkhart is suspected of setting more than 50 blazes that caused an estimated $3 million in damage. He has refused to cooperate with investigators since his arrest on Monday.

The arson was allegedly caused by the use of a device designed to accelerate the fire. Court documents revealed an incendiary device was placed under the engine area of cars.

Burkhart has retained a public defender and is using a German interpreter in court. Burkhart is due back in court on Jan. 24.

Authorities said they believe he was angry over his mother's legal troubles and went on a nighttime rampage of burning parked cars a day after she appeared in court last week.

Burkhart has been put on suicide watch, a law enforcement official said Wednesday. The official spoke on the condition of anonymity because of privacy issues.

Burkhart's mother Dorothee Burkhart said in court Tuesday that her son is mentally ill.

Burkhart is also under investigation in his home country of Germany for a house fire north of Frankfurt days before he traveled to the U.S. in October.

The fire at the house, which belonged to the Burkhart family, has been ruled an arson, Marburg prosecutors' spokeswoman Annemarie Wied told The Associated Press Wednesday.

Burkhart did not live in the area, but his name surfaced as a suspect after he filed an insurance claim shortly after the fire, Wied said.

"When one files an insurance claim on a house the same day it burns down, it raises eyebrows," she said.

Burkhart, whom Wied identified only as "Harry B." in keeping with German privacy laws, has not yet been questioned in the case and no arrest warrant has been issued for him. She said she did not know how long ago he had been identified as a suspect in the arson investigation.

Burkhart was in Los Angeles by Oct. 26 -- 12 days after the Marburg area fire -- according to U.S. court papers, which say that he went with his mother on that day to the German consulate to renew his passport.

During a court appearance in federal court Tuesday, Burkhart's mother, Dorothee Burkhart, scanned a Los Angeles courtroom looking for her son, apparently unaware he was also behind bars less than two miles away.

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

Court documents were unsealed Tuesday that revealed she 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.

In a brief court appearance, 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.

"What did you do to my son?" she asked U.S. Magistrate Judge Margaret Nagle.

"I'm not here to address anything related to your son," Nagle responded.

Frankfurt court spokesman Guenther Meilinger told the AP that Dorothee Burkhart will go on trial for the fraud charges once she is extradited back to Germany.

"We expect and hope that the U.S. authorities will look into the request for extradition ... so that the proceedings against her can continue," he said.

Both mother and son are being held without bail. Her next court hearing was delayed until Friday so she can hire an attorney, and charges could be filed against Harry Burkhart as early as Wednesday.

Harry 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.

Burkhart's non-immigrant 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.

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, which is 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 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 against anyone or property at his mother's court hearing.

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.

Fox News' Lee Ross and the Associated Press contributed to this report.