Egypt's top prosecutor levied charges on Wednesday against nine policemen over an assault on physicians at a Cairo hospital earlier this year.

The defendants are accused of the "unauthorised detention of two doctors," physical and verbal assault, cruelty and misuse of power.

The charges stem from an attack on 28 January by several low-ranking policemen against doctors at Matariya Hospital in eastern Cairo, after one of the doctors refused to include fake injuries in a medical report for one of the policemen.

The incident prompted thousands of doctors to protest in February at the Doctors Union, calling for the prosecution of the assailants and the resignation of the health minister.  

The protest was believed at the time to be one of the biggest demonstration by union members the country had seen since President Abdel-Fattah El-Sisi took office two years ago.

Eyewitnesses said that two plain-clothed policeman assaulted the two doctors, kicking one in the stomach and stepping on his neck when he resisted, before taking him and his colleague to a nearby police station.

According to testimonies, the policemen were later joined by seven of their colleagues who arrived at the scene from the police station

One of the doctors, Moamen Abdel-Azim, said at the time that he had to withdraw an official complaint he had filed at the station for fear of retaliatory detention after the officers filed a counter-complaint against him, accusing the physicians of assault.

The first hearing for the trial is due on 25 May.

Human rights groups say that police violations, which were a main catalyst for the 2011 popular uprising, remain widespread.

President El-Sisi called on the interior ministry in February to crack down on police abuse and submit legislation to parliament to address the issue.

In April, a policeman shot dead a street vendor in a personal dispute in a suburb of  Cairo, provoking an impromptu protest by dozens of angry vendors.

Also in April, a policeman was handed a life sentence for shooting dead a driver in a personal argument over a business transaction. In February, a police officer in the north-eastern city of Ismailia was sentenced to eight years in prison on charges of beating a veterinarian to death while in custody.