Confederate battle flags were stealthily placed on the grounds of the Rev. Martin Luther King Jr.’s church, and authorities said Thursday they were looking for two white males who were recorded on surveillance camera leaving the banners behind. Atlanta police Chief George Turner said his agency was working with federal authorities and they have not determined what charges might be levied. Turner said they have not ruled out a hate crime. An officer from the Atlanta FBI’s joint terrorism task force was on the scene “to better determine if any specific threats were received” and to provide support to Atlanta police, the FBI informed in an email.