Hosni Mubarak's two sons were accused Wednesday with insider trading in a new case opened just three days before they and their elderly father are to hear the verdict in a separate trial on charges of corruption and complicity in killing protesters during last year's uprising.

The prosecutions of the Mubarak family and its cronies had seemed to be part of a process of dismantling the old regime ousted in the uprising. But now Mubarak's last prime minister and longtime protege is one of two candidates heading into a runoff vote for president in just a few weeks.

The new case, which was referred to trial, was interpreted as a timely attempt by Egypt's military rulers to assuage anger over the possible ascent to the presidency of Ahmed Shafiq, the last prime minister to serve under Mubarak and, like his mentor, a former air force commander. Shafiq is widely viewed as an extension of the Mubarak regime remembered for authoritarianism, corruption and a brutal police force.

"It's an attempt to ease the popular anger over Shafiq," said Shady el-Ghazali Harb, a key leader of the anti-Mubarak uprising. "It is a theatrical move by the generals to create the illusion that there is no question of showing leniency to the old regime."

Mubarak and his two sons, the one-time heir apparent Gamal and wealthy businessman Alaa, are already on trial for separate charges of corruption. They have all been in prison since April 2011, two months after a popular, 18-day uprising forced Mubarak to step down after 29 years in office.

Mubarak, 84 and ailing, faces additional charges of complicity in the death of some 900 protesters during the uprising. But his sons are not charged in the protester killings. The former leader could get the death penalty if convicted on the charges linked to killing protesters.

A statement by the prosecutor-general's office on the new charges said the Mubarak sons, along with seven others, made 2 billion Egyptian pounds in illicit gains. Their actions violated central bank and stock market regulations, it said.

The nine are accused of conspiring to stealthily buy a controlling 80 percent stake in Watan Bank in 2006 without declaring their share to the stock market authority, it added. They later traded its shares through closed funds and investment companies based abroad.

"They deliberately withheld this essential information on the sale of the bank from other share traders to execute their criminal plot and violate the principles of transparency and equality between traders," said the statement. It did not specify the role of each of the nine defendants nor announce a date for the trial.

The seven other defendants are free on bail but banned from leaving the country.

The prosecutor's statement said Gamal, 48, unlawfully made a profit of nearly 500 million Egyptian pounds from the sale of the Watani Bank and that his brother Alaa, believed to be around 50, used insider information about the bank to reap an illegal profit of some 12 million Egyptian pounds.

Two of the seven men charged along with the Mubarak sons are chief executives at Hermes, one of the Middle East's top investment banks with branches in nine Arab nations. They are Yasser El-Malawny and Hassan Heikal, son of Mohammed Hassanein Heikal, Egypt's best known political writer and a longtime confidante of the late Egyptian leader Gamal Abdel-Nasser.

The three Mubaraks, along with the ousted leader's security chief and four of his top aides, will hear the court's verdict on the case already in progress on June 2.

Gamal Mubarak was viewed by many as a corrupt politician who used his father's position to illegally amass a fortune while working along with a coterie of regime-backed wealthy businessmen and powerful politicians to ensure that he succeeded his father.

He rapidly rose to the top of his father's ruling National Democratic Party to become its de facto boss on the eve of his father's ouster, when he also was effectively running Egypt's day-to-day affairs. At the time of the uprising, there was growing anxiety in Egypt that his succession was imminent. That anxiety is seen as one of the key sparks for the uprising that overthrew Mubarak.

Many of Gamal's closest allies are among some three dozen regime stalwarts in detention facing charges of corruption. Some of them have been convicted and sentenced to prison terms.

The new charges came two days after Shafiq was officially declared one of two top vote-getters in the first round of presidential elections held on May 23-24. Shafiq and the Muslim Brotherhood's Mohammed Morsi will now go head-to-hear in a runoff vote on June 16-17. The winner will be announced June 21, the last step before the generals are due to hand over power.

A Shafiq presidency would mean the continuation of de facto military rule in Egypt, where all four presidents since the overthrow of the monarchy nearly 60 years have been of military background.

Shafiq's qualification to the runoff has angered many Egyptians who see him as an extension of the old regime and an affront to the uprising that, among other things, sought to end military rule. Several hundred protesters stormed, vandalized and set ablaze his campaign headquarters in Cairo late on Monday night, just hours after the official results were announced.

Other protesters in Cairo and a string of cities in northern Egypt tore down his campaign posters.

Michael Hanna, an Egypt expert from the New York-based Century Foundation, said the announcement of new charges is the latest measure by the ruling generals who took over from Mubarak against their old regime rivals — Gamal Mubarak, his brother along with the businessmen and politicians who threw their weight behind the succession scheme. The military primarily opposed the succession because it would end the military's decades-old grip on the land's highest office.

"Today's announcement fits a pattern of prosecuting politicians and businessmen viewed by the military as a threat to its interests when it has been nearly impossible to convict policeman accused of killing protesters."

Earlier Wednesday, a criminal court convicted and sentenced to five years in prison a policeman for his part in the shooting death of 18 protesters on January 28, last year, the bloodiest day of the uprising. Mohammed el-Sunni had been sentenced to death earlier when he was on the run. Thursday's verdict came after a retrial that followed his surrender to authorities.

But his conviction followed multiple court cases in which policemen charged with killing protesters have been acquitted or received light sentences.