CAIRO, Egypt - Hosni Mubarak's trial on charges he ordered the killing of protesters during Egypt's uprising will be held at a police academy on Cairo's outskirts instead of a convention centre in the heart of the capital, the head of Cairo's appeals court said Saturday.

The change appears to be linked to concerns over security during the ousted leader's trial, which is scheduled to begin Wednesday and is sure to draw a large audience. The 83-year-old ex-president is to stand trial alongside his security chief and six other senior security officials facing the same charges stemming from the crackdown that killed hundreds but failed to stop the 18-day uprising that forced Mubarak from power on Feb. 11.

Mubarak's two sons are also expected to appear in court on corruption charges. A business associate will be tried in absentia.

Keeping order during the trial is a top concern. Protests have escalated recently as Egyptians demand faster changes and the prosecution of Mubarak and former regime officials from the military leaders who have taken temporary control of the country.

In recent days, violence has also flared in Egypt's desert Sinai Peninsula, a restive area of the country that has grown more so since Mubarak's overthrow. On Saturday, gunmen detonated a bomb at an empty terminal along Egypt's natural gas pipeline to Israel.

That attack followed more than six hours of clashes overnight between Islamic militants and security forces in the nearby city of el-Arish that killed six people, including a military officer, a policeman and a teenager.

The police academy is located in New Cairo, a district on the capital's eastern edges that is not as heavily populated as the area around the convention centre. The change in venue was announced by Judge El-Sayed Abdel-aziz Omar, who according to law is in charge of deciding the trial location.

After his overthrow, Mubarak left Cairo for the Sinai resort city of Sharm el-Sheikh. He was later admited to a hospital there for treatment for heart problems. He has remained at the hospital in police custody.

Frequent reports that Mubarak's health has been faltering have raised speculation that the trial would be held in Sharm el-Sheikh, that it could be delayed or that Mubarak might not appear in court.

Most recently, doctors treating Mubarak have said he is weak and has lost weight from refusing to eat. They have also said he suffers from severe depression.

Activists believe Mubarak's health is being used as an excuse to postpone the proceedings and they accuse the ruling military council, whose head was Mubarak's defence minister, of dragging its feet on the prosecution of the ex-president and other members of his regime.

Protests in Cairo's Tahrir Square and other parts of the country are clamouring for Mubarak and other former regime stalwarts to be brought to justice over the killings of nearly 900 protesters during the uprising and other crimes over the years.

The attack on the gas pipeline to Israel was the third time it has been targeted this month. No gas has been flowing through the pipeline since the last attack, on July 12. No one was injured in the latest attack.

Also in the northern Sinai, gunmen wounded a policeman Saturday in a drive-by shooting in the city of el-Arish, a security official said, speaking on condition of anonymity because they were not authorized to brief the media.

A day earlier, the heavily armed militants paraded around town in a show of force, firing in the air and damaging a statue of late President Anwar Sadat, who signed Egypt's peace deal with Israel over 30 years ago. They also attacked a police station.

There was no immediate claim of responsibility for the attacks in el-Arish, but officials blamed a militant Bedouin group. Security forces arrested five suspects.

The Bedouin group has clashed with security forces in northern Sinai since the uprising that toppled Mubarak.