Months after an uprising ended his 30-year-rule, Egypt's ex-president Hosni Mubarak goes on trial Wednesday on murder charges, in a historic moment for the Arab region whose leaders are rarely held to account.

Mubarak arrived at the Police Academy in a Cairo suburb where he is to face trial accused of murder and corruption, shortly after being flown to the Almaza military airport in Cairo.

Television footage showed an ambulance driving up to the courthouse, amid intense security and a heavy army presence.

Mubarak's court appearance will be his first since he was ousted on February 11.

Barbed wire was erected outside the Police Academy and more than a dozen riot police trucks secured the entrances, an AFP reporter said.

Dozens of Mubarak loyalists clashed briefly with opponents outside the court, pelting each other with stones, before being quickly separated by security forces.

The former president, 83, is due in court at the police academy in a Cairo suburb along with his two sons Alaa and Gamal amid one of the biggest security operations in the country's recent history.

The trial is being held in an auditorium fitted with a large black cage to hold the defendants, including former interior minister Habib al-Adly, on whom Mubarak relied to quell the revolt that overthrew him, and six police chiefs.

Businessman Hussein Salem, a close associate of the Mubaraks, is being tried in absentia.

The defendants are accused of stealing millions of dollars from the state and ordering the killing of anti-regime protesters during the January 25 uprising that led to the downfall of the Mubarak regime.

More than 1,000 police and soldiers are securing the complex and vetting about 600 lawyers and journalists granted permission to attend.

Mubarak will also face some relatives of the victims killed during the revolt, allegedly on his orders.

He has been under arrest for several months in a hospital in the Red Sea resort town of Sharm el-Sheikh, where he is being treated for a heart condition.

For weeks, it seemed likely that Mubarak, who doctors say refused to leave his hospital bed, would be tried in Sharm el-Sheikh, but the justice ministry announced last week the trial would be held in Cairo.

His lawyer, Farid al-Deeb, will argue that Mubarak is too sick to stand trial and that he did not sanction the brutal crackdown on protesters that left more than 850 people dead by the time Mubarak resigned on February 11.

Deeb claimed that Mubarak suffers from cancer and went into a coma last month, which the hospital denied. One of his doctors told AFP the ex-president was stable, but extremely depressed and weak after refusing food for several days.

Deeb's announcements appear to have been intended to increase sympathy for Mubarak and spare him the indignity of appearing in the defendants' cage.

But the interior and health ministers have both said they were preparing to ensure Mubarak's attendance, which would go a long way toward assuring sceptics that he will face justice.

The military, which assumed power after Mubarak's resignation, is keen to prove it harbours no lingering loyalties to the former president.

The trial will be the latest in a string of legal proceedings against members of the Mubarak era.

Several ministers have already been sentenced to jail in corruption cases, including Adly, sentenced to 12 years in jail for corruption.

Mubarak is the second Arab leader to be overthrown in the unrest that has swept North Africa and the Middle East since the beginning of this year.

Tunisian president Zine El Abidine Ben Ali, who fled his country in January after a popular revolt, has already been twice convicted and sentenced in absentia for possession of arms, drugs and archaeological artefacts and for misappropriating public funds.

On Tuesday, international rights groups urged a "fair and transparent" trial.

"This trial presents a historic opportunity for Egypt to hold a former leader and his inner circle to account for crimes committed during their rule," said Malcolm Smart, Amnesty International's director for the Middle East and North Africa.

"If these proceedings scrupulously reflect the international fair trial standards, it will embody a clean break with the record of impunity that characterised Hosni Mubarak's rule, contribute to a new and hopeful chapter in Egypt's history, and set an important regional precedent," said Sarah Leah Whitson, Middle East and North Africa director at Human Rights Watch.