A teacher at a school where a student allegedly set fire to an English language version of the Koran fears extremists may now "jump on a bandwagon".
The 15-year-old schoolgirl was arrested on suspicion of inciting racial hatred on November 19.
West Midlands Police said the pupil, who was later bailed, was accused of setting fire to the booklet at an unnamed school in the Sandwell area, and posting the footage on Facebook.
A 14-year-old boy was arrested on Tuesday on suspicion of making threats on the social networking site, in connection with the alleged incident. He was later released on bail.
A senior teacher at the school told the BBC: "I'm very concerned over the wider impact of this in terms of people with extreme views may choose to jump on a bandwagon. That is my deep-seated fear at this moment in time."
He said the schoolgirl "did not realise exactly what she was doing", adding: "If she stopped to consider the fallout of doing this kind of thing, and she considered the offence it would cause to people within her own community in the school, I honestly don't believe she would have done it."
A police spokeswoman said: "The local neighbourhood team have strong links with the school and have been working closely with key partners from the community and the local authority to resolve the matter locally.
"West Midlands Police will investigate and monitor any crime reported by individuals who may have been targeted because of their disability, gender, race, religion or belief, sexual orientation or transgender."
Councillor Bob Badham, Sandwell Council's cabinet member for children and families, said: "The council has been working hard with a school, police, and the local community to maintain harmony following an incident earlier this month.
"All involved have reacted very positively".