CAIRO, Egypt (AFP) — Egyptian authorities have decided to put on trial a Salafist ex-MP who was caught allegedly performing an "indecent" sexual act with a woman in public, a judicial source said yesterday.

Ali Wanis's trial is set for Sunday and will take place on time although he has gone missing since police found him last month engaged in a sexual act with a 22-year-old woman in a car parked on a highway.

The woman, a university student, is behind bars and the public prosecutor's office has ordered the arrest of Wanis, a cleric and former MP for the ultra-conservative Al-Nur party.

After the incident in early June, Wanis denied any wrongdoing and said in a video posted on his website that he had parked along the side of the road because his passenger "became sick."

But the pair have been accused of performing an "indecent" sexual act in public.

Al-Nur party, which represents the conservative Salafi brand of Islam, won the second largest number of seats in parliamentary elections last winter after the Muslim Brotherhood.

It was hit with a scandal in March when another lawmaker was forced to resign from parliament and from his party after claiming he was injured in a carjacking — to explain bandages on his face — when in fact he had had a nose job.

Last month, Egypt's constitutional court ruled that a third of the parliament had been elected illegally and ordered the entire body dissolved.