A Swiss woman undergoing psychiatric treatment showed no remorse on Monday when she went on trial accused of trying to murder two women in the name of the Islamic State (IS) group.

The woman, who cannot be named for legal reasons, is accused of committing a "terrorist act" on November 24, 2020 - a knife attack in the plush Manor department store in Lugano, in southern Switzerland's Italian-speaking Ticino region.

One of the two victims - who was attending the trial - suffered a serious neck injury. The second sustained wounds on one hand and managed, with others, to control the assailant until the police arrived.

"If I could go back, I would do it better... with accomplices," the 29-year-old told Switzerland's Federal Criminal Court in Bellinzona, also in Ticino.

Having discovered the IS jihadist group on social media, she said she had planned for "months, years" to "do something" for IS and show that she was "capable of carrying out a terrorist act."

A photograph of the neck injury was shown to the court.

"It didn't go as deeply as I thought," the accused woman observed, before repeating, "It has no effect on me."

Dressed in black, in accordance with court rules, the accused wore a long tunic, tights, a black face mask and a hoodie.

She wanted to keep her head covered, saying, "I'm Muslim," before agreeing to lower the hood to comply with court rules.

According to the indictment issued by the Office of the Attorney General of Switzerland, the accused "acted wilfully and with particular ruthlessness."

It is alleged that she shouted "Allahu akbar [God is greatest]" several times and "I will avenge the Prophet Mohammed," and declared "I am here for IS."

During the opening hearings, the accused woman answered questions posed by the presiding judge. Three justices are hearing the trial.

The daughter of a Swiss father and a Serbian mother, the woman said she suffered epileptic seizures during her early childhood.

Her adolescence was marked by anorexia. She did not attend secondary school.

The woman had work experience as a sales assistant and a hairdresser.

The suspect has been in contact with psychologists and psychiatrists since her childhood. She said she is being seen in custody, where she is undergoing treatment that makes her "nervous."

She said she became pregnant at 17 by her future husband, a man of Afghan origin, whom she married aged 19. The pair divorced in 2021.

"It started well, then things went badly," she said, explaining that her husband did not want her to study or have an abortion.

She was unwilling to take care of the baby, which was adopted by her parents.

Psychiatrist Carlo Calanchini told the court that the suspect suffers from "slight mental retardation" and disorders similar to schizophrenia, with a particular lack of empathy.

He strongly doubted that she would ever develop a "better capacity for judgement" and estimated that she actually knew very little about jihadism - and much less than anyone who read the newspapers.