He even blamed himself for any rough police treatment, saying that in his confusion he was resisting them.
"I was afraid. ... They were telling me: 'We swear to God we will not harm you, don't be afraid,'" Saber said, adding, "I was being very tiresome to the police."
His wife also praised the police, telling state TV, "they are giving him good treatment" at the police hospital.
But his children said their father spoke under duress.
"There are pressures on my mother to say that he is fine," daughter Randa told independent Dream TV. "The government is the one pressing him."
In a statement, the Interior Ministry voiced its "regret" about the assault and vowed to investigate.
Interior Minister Ibrahim echoed Saber's account, saying an initial investigation showed it was protesters who stripped and beat him. Ibrahim said riot police found Saber and were only trying to get him into the van, "though the way they did it was excessive."
On Sunday, Saber acknowledged that it was indeed police who beat and stripped him. Speaking to Al-Hayat TV, he said he gave his initial account because was afraid, then broke down in tears as he recounted begging the policemen for mercy.
"But no one gave me mercy," he wept. "My whole body was smashed." He has now been moved to a civilian hospital.
Rights activists say police intimidation of victims and their families to prevent complaints was rife under Mubarak and continues unabated. In a report last month, the Egyptian Initiative For Personal Rights documented 16 cases of police violence in which 11 people were killed and 10 tortured in police stations. Three died under torture during the first four months after Morsi took office on June 30, it said.
The rights group said officers increasingly act "like a gang taking revenge."
In one case it documented, police in the Nile Delta town of Meet Ghamr stormed a cafe and beat up patrons in September. When a woman who was beaten went to the police station to complain, the man accompanying her was arrested and tortured to death, the report said.
The sister of the slain man told AP that her brother's widow was paid the equivalent of around $25,000 to say that he was killed by a rock to his head during a protest.
"The main issue is that nothing has changed about the police. No change about accountability. There is just as much impunity as there was under Mubarak," said Heba Morayef of Human Rights Watch. Over the past two years "we've seen an increase in the likelihood police will use lethal force ... in the context of regular policing activities."
In the case of el-Gindy, the activist who died Monday, fellow activists say he disappeared during a Jan. 27 Tahrir protest and they later learned from people who left the Red Mountain security camp that he was being held there. Soon after, el-Gindy was brought to a hospital in a coma and died Monday.
After his burial in his hometown of Tanta in the Nile Delta on Monday, angry mourners marched on police headquarters and clashes erupted, with protesters throwing firebombs and stones and police firing back tear gas.
At a funeral ceremony held earlier at a mosque in Cairo's Tahrir Square, there was widespread skepticism that anyone would be held accountable for el-Gindy's death.
"So this blood will be wasted so easily?" one woman in black screamed.
"It will be lost," an elderly man responded. "Like others were before."
AP reporter Amir Maqar contributed to this report.
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