Harry Burkhart, 24, was held without bail and was scheduled for arraignment in court Wednesday morning.
Investigators are looking into the possibility of more suspects in the case.
Burkhart was pulled over near Sunset Boulevard and Fairfax Avenue about 3 a.m. Monday. Explosives materials were reportedly found in his vehicle. He was detained less than 24 hours after police released surveillance video of a man walking away from the scene of an arson fire set in a parking structure near Hollywood and Highland.
Authorities believe Burkhart is responsible for setting more than 50 fires in and around the Hollywood area. He was charged with a felony count of arson, but more charges were expected.
There were no suspicious fires reported after Burkhart was arrested.
No one was seriously injured in the fires, but dozens of cars were destroyed and property was damaged. Damage is estimated at $3 million.
A motive has not yet been determined, but Burkhart's mother, Dorothee Burkhart, was facing deportation back to her native country Germany. She was arrested last week. At her detention hearing last week, Harry Burkhart reportedly loudly voiced obscenities and anti-American sentiments. He was escorted from the courthouse.
Dorothee Burkhart was held at the Los Angeles County Jail. She made a court appearance Tuesday.
She sat in the courtroom, demanding that her handcuffs be removed. Then, seeming perplexed, she repeatedly asked the judge where her son was, wondering aloud if he was dead or had disappeared.
"The indication that I got from that is that she does not know her son has been taken into custody," said Justice Department spokesperson Thom Mrozek.
At one point in the hearing, she said her son was mentally ill and that he may have been taken by German Nazis.
Dorothee Burkhart faced deportation on 19 charges of fraud in Germany, including failure to pay for breast augmentation and failure to return security deposits on apartments she rented to tenants.
She is also behind an erotic website called HollywoodTantraMassage.com, which offers male clients over the age of 23 sensual massage, but states the service is not prostitution.
Dorothee Burkhart is scheduled to appear in court again on Friday.
Harry Burkhart lived in one-bedroom apartment in Hollywood with his mother. When he was detained, he told investigators that he hates America, according to ABC News.
Shervin Lalezary, who has worked as a volunteer reserve sheriff's deputy for three and a half years, pulled over Burkhart's minivan. Lalezary said he recognized Burkhart from the surveillance video, but said he couldn't take all the credit.
"It's a team effort. I think the gratitude goes to all the agencies involved, all the deputies involved," Lalezary said. "I'm ecstatic that law enforcement gets to shine a little because I feel like sometimes we're put in a negative light because of the nature of our job, and every once in a while law enforcement gets a thumbs up. I'm glad for law enforcement."
Authorities said they would have a better understanding if Burkhart acted alone after they conduct a thorough search of his home.