Last Wednesday, the 19-year-old Kaulitz was caught on tape throwing a lit cigarette at the 21-year-old woman, before punching her in the face and throwing her to the ground at a Hamburg gas station. Kaulitz, who headlines the band with his twin brother, Bill, then sped off in his Audi R8.

According to Bild, the woman belongs to a French stalker gang called “The Afghans on Tour.” The gang has four members, all women, who wear masks or wrap their faces in scarves. A profile of a 23-year-old woman from Hamburg on the MySpace that’s listed with the same name shows photos of a woman with her face wrapped in a Palestinian scarf.

The gang sent threatening letters to the group, including one seen by Bild that promised “a little nightmare” for Tokio Hotel and went on to say, “Caution, caution. We’re unhappy. We’re getting impatient. DO YOU UNDERSTAND US?”

The gang has also staked out houses where band members live, thrown eggs at their cars and threatened members of the band’s family, the newspaper reported. After a threat against Kaulitz’s mother, the band filed for a restraining order against members of the gang.

Hamburg police reported last week they were investigating Kaulitz for possible charges of bodily harm.

Tokio Hotel released their first album “Schrei” (Scream) in May 2006 and sold some 600,000 copies in six days in Germany. The Magdeburg-based teen group also quickly became a major success in France, Austria and Switzerland. The band’s first US single was released in late 2007.