A woman who allegedly set fire to a teenage girl’s hair and then disappeared on a bus in Adelaide is still being sought after two months later.

THe alleged attack took place in Elizabeth around 3:30 pm on June 29.

The woman is accused of sitting behind a 13-year-old schoolgirl and setting her hair alight.

“(The girl) didn’t know this woman, there was no conversation had between them,” South Australia Police senior constable Matt Styles said.

“She’s reacted based on the pain she felt to the back of her head.”

The alleged attacker has just run off the bus after the alleged attack.

“We’ve lost her on camera and lost her on CCTV,” Mr Styles said.

The teenager is still suffering trauma as a result.

“Already there’s trauma attached to the incident,” he said.

“Potentially we could go physical, mental and emotional trauma, and that’s the sort of stuff that leaves scars for a long time.”

The woman accused of the attack is described as being aged between 50 and 60.