A TUNISIAN feminist who scandalised her country by posting topless photos of herself online has been arrested after allegedly sneaking into Tunisia's holiest city disguised in a veil, then trying to get undressed during a protest.

On Sunday, Amina Tyler - a 19-year-old member of the Ukrainian feminist group FEMEN, which uses nudity in its protests - passed through heavy security and checkpoints to enter the city of Kairouan, where police were preventing hardline conservative Islamists from holding an annual conference.

There she unveiled her bleached blonde hair and cutoff jeans, scrawled "FEMEN" on the wall of a cemetery near the city's main mosque, and attempted to take off her clothes, her lawyer Radhia Nasraoui quoted police as saying.

The protest enraged local residents who converged on her, and police took her into custody.

In a video of the incident shown on the Tunisian news website Nawaat, people yell "get out" at her as police usher her into a waiting van.

"She is dishonouring us. We will protect our town, but a dirty girl like her shouldn't come among us," one resident screams at the camera.

"We are all Muslims," Tyler says to one man, who replies: "You are no Muslim. Don't come to Kairouan."

The Interior Ministry said on Monday she might be charged with conducting "provocative acts" when she appears in court on Tuesday.

"It is an act of provocation and it is against the morals and traditions of Tunisian society, which is a Muslim society," Interior Ministry spokesman Mohammed Ali Aroui told journalists, without elaborating on what those acts were.

Her mother, Wafa, told The Associated Press her daughter needed help and was being treated by a psychiatrist.

"She suffers from psychological problems," she said on the phone, tearfully. "I am very worried for my daughter. I'm afraid she will be condemned by the court."