(CBS/AP) -- A man was offered $200 to beat a transgender woman in an attack that was recorded as a crowd gathered to holler and watch, police said in an affidavit released Monday. The woman, Muhlaysia Booker, accidentally backed into a vehicle before the driver of that vehicle pointed a gun at her and refused to let her leave unless she paid for the damage, police said.
Police said as a crowd gathered, someone offered $200 to 29-year-old Edward Thomas to beat the woman.
A bystander recorded cell phone video as Booker lay on the ground while men punched and kicked her, and others looked on. Several women eventually intervened and dragged her to safety. Booker suffered a concussion, fractured wrist and other injuries.
Police said a second person stomped on the woman's head in Friday's attack but hasn't yet been charged.
LGBTQ community advocates expressed outrage over the attack and over the crowd that stood by without aiding the woman.
Thomas was being held Tuesday at the Dallas County jail on a charge of aggravated assault causing serious bodily injury. Jail records don't indicate whether he has an attorney.
Police say they are investigating the attack as a possible hate crime, and are working with the FBI to determine whether the case can be charged under federal hate crime statutes, CBS Dallas reported. Last year, the FBI reported hate crimes increased in 2017 for the third year in a row.
Booker's father, Pierre Booker, told the station the attackers were "cowards" and his daughter "is traumatized from it. Very traumatized."
He said the attack has left him "highly upset" and that he hated watching his daughter being assaulted.
Dallas Mayor Mike Rawlings said he is "extremely angry about what appears to be mob violence against this woman" and that those responsible don't represent how most residents feel about the city's "thriving LGBTQ community."