Authorities say a German suspect is on suicide watch after he was charged with multiple counts of arson in connection with more than 50 deliberately set fires in Los Angeles.

Harry Burkhart was arrested Monday. He is accused of going on a four-day arson rampage that investigators say caused about $3 million in damage. He has refused to cooperate with the investigation.

Prosecutors in his native Germany say the 24-year-old Burkhart also is under investigation for suspected arson in a house fire in a town near Frankfurt .

Los Angeles authorities say they believe Burkhart began setting the L.A. fires in anger over the arrest of his mother.

The first of the blazes broke out Friday, the day after 53-year-old Dorothee Burkhart appeared in court for a hearing. She was arrested under an international warrant, and is facing 19 counts of fraud and embezzlement.

At her court appearance Tuesday, Ms. Burkhart asked why her son was not present, apparently unaware he had been arrested. She told the federal judge her son was mentally ill. She also speculated that the Nazis had discovered their address.

Most of the arson attacks targeted cars parked either outside homes or in parking structures. No one was killed or seriously injured in the arson spree. Authorities are looking into whether other suspects were involved.