The ruling marks another major setback for the young activists who spearheaded the Arab Spring-inspired uprising nearly four years ago — many of whom are now in jail or have withdrawn from politics. It will likely reinforce the perception that Mubarak's autocratic state remains in place, albeit led by a new president, former military chief Abdel-Fattah el-Sissi.

Saturday's verdict concludes Mubarak's retrial along with his two sons, his security chief and six top security commanders, who were all acquitted. Also acquitted was businessman Hussein Salem, a longtime Mubarak friend tried in absentia.

Mubarak, 86, was also acquitted of corruption charges that he faced along with his sons Alaa and Gamal.

All rulings can be appealed.

It was not immediately clear whether Mubarak would now walk free since he is serving a three-year jail term for corruption charges he was convicted of in May. He has been in detention since April 2011, but it is unclear if the past 3 1/2 years will be considered as time served.

"There is no justice for the poor," said Ramadan Ahmed, whose son Mohammed was shot dead in the Mediterranean port city of Alexandria during the uprising. "This is Mubarak's law!"

Nearly 900 protesters were killed in the 18-day uprising that ended when Mubarak stepped down on Feb. 11, handing over power to the military. The trial, however, was concerned only with the killing of 239 protesters, whose names were cited in the charges sheet.

The early days of the protests were marked by fierce street battles between the demonstrators and both police and government supporters. Vehicles plowed into crowds, and bricks and stones were hurled from the rooftops of buildings onto demonstrators gathered in Cairo's Tahrir Square. At one point, men on camels and horses galloped into the square and beat protesters with batons and whips.

Nearly 170 police officers and security officials put on trial in connection to the killings since 2011 have either been acquitted for lack of evidence or because they were found to have acted in self-defense. Some received short, suspended sentences.

Mubarak was convicted and sentenced to life in prison in 2012 on charges related to the killing of protesters, but the verdict was overturned on appeal the following year.

Mubarak has spent virtually all the time since he was detained in hospitals due to poor health. On Saturday, he was brought to the defendants' cage on a gurney. He wore dark glasses, a navy blue tie and a matching cardigan.

Presiding judge Mahmoud al-Rashidi made clear that the dismissal of the charges did not absolve Mubarak of the corruption and "feebleness" of the latter years of his 29-year rule and praised the 2011 uprising, saying that its goals — freedom, bread and social justice — were legitimate.

Al-Rashidi said Mubarak, like any other human, erred at times and suggested that his old age should have spared him a criminal trial. He also cited Mubarak's long years in public service and what he called the enshrinement of "constitutional legitimacy" following the ouster of Mubarak's successor, the Islamist Mohammed Morsi.

Mubarak was a career military pilot who led the air force during Egypt's last war against Israel in 1973. He was made vice president in the mid-1970s and assumed the highest office in 1981 following the assassination of Anwar Sadat.