What to Know An investigation is underway after a flash mob was caught on video attacking and robbing two teen girls and two teen boys in Center City.

One of the victims, a 17-year-old girl, told NBC10 she and three of her friends were attacked by a group of at least 20 teens.

Investigators told NBC10 it was the latest of a series of reported incidents of a group of teens attacking people in Center City.

An investigation is underway after a flash mob was caught on video attacking and robbing four underage teenagers in Center City.

One of the victims, a 17-year-old girl who did not want to be identified, told NBC10 she and three of her friends - another girl and two boys - were getting food at the Wendy's restaurant on 15th and Chestnut streets Monday around 6:30 p.m. when they were suddenly attacked by a group of at least 20 teens.

"I remember them saying, 'Get her.' And then the next thing I know, my face was burning and bubbling," the girl said.

The teen told NBC10 the group beat her, used pepper spray on her and stole her phone, wallet and ear buds.

"I could feel people violating me and in my pockets and taking all my stuff," she said.

Investigators told NBC10 it was the latest of a series of reported incidents of a group of teens attacking people in Center City. NBC10 obtained cellphone footage showing the attack. Tamieka Daniels, the mother of one of the victims, was in tears as she watched it.

"That's my son fighting for his life," Daniels said.

No arrests have been made. Anyone with information on the attacked is asked to contact the Philadelphia Police Department.