Former Egyptian President Hosni Mubarak was abruptly hospitalized Tuesday for heart problems during an investigation over allegations of corruption and violence against protesters, reported state TV.

In a sign that his ailment might not be very serious, however, Justice Minister Mohammed el-Guindi said the former president was now being questioned in the hospital.

The 82-year-old Mubarak was deposed Feb. 11 after 18 days of popular protests and has been under house arrest in the Red Sea resort of Sharm el-Sheikh for the last two months. The public prosecutor announced Monday he was under investigation.

Dozens of demonstrators picketed the hospital, denouncing the president and carrying a sign reading "Here is the butcher." They scuffled briefly with supporters of Mubarak amid a massive security presence.

El-Guindi said Mubarak was being investigated over his role in the violence against protesters during the uprising in which more than 800 people died. The investigation into corruption charges would be carried out later by the Justice Ministry's anti-corruption department, he said.

An investigation of Mubarak's son, Gamal, is also underway in Sharm el-Sheikh, the minister added in comments carried by Egypt's state news agency.

Deciding on the site for the interrogation was a dilemma for the authorities who wanted to grant the ailing president a degree of privacy and security.

Mubarak arrived under heavy police protection to the main hospital and stepped out of his armored Mercedes unaided before being taken to the presidential suite in the pyramid-shaped building, according to doctors and security officials at the hospital who spoke on condition of anonymity because they were not authorized to speak to the media.

The protest movement that deposed Mubarak is now pushing for him to be brought to justice for what they say are decades of abuse. Since Friday, hundreds reoccupied parts of Tahrir Square in downtown Cairo.

The protesters had criticized the army for being too close to the old regime and not swiftly bringing Mubarak to trial.

On Tuesday, however, a scuffle broke out when some residents tried to break up the four-day sit-in, removing barbed-wire and barricades. The army then moved in and took control of the square and cordoned off the once grassy roundabout that had been the center of many demonstrations.

Sanaa Seif, a 17-year-old on the scene, said she saw the army forcibly remove people and the state news agency confirmed that the military police had detained a number of "outlaw thugs" at the square.

Mubarak has a history of minor ailments and underwent gallbladder surgery in Germany in March last year.

He has kept a low profile since he was ousted, living on his compound in Sharm el-Sheikh. He was banned from traveling and his assets have been frozen. Many of his senior aides have already either been questioned or detained pending investigations.

Egypt's state TV reported that Safwat el-Sherif, a senior aide of Mubarak and one of the most powerful men in his regime, was ordered detained for an additional 15 days pending investigations into his role in attacks on protesters during the uprising.

El-Sherif had already been remanded into custody for 15 days for the corruption probe.

On Sunday, Mubarak defended himself in a pre-recorded message saying he had not abused his authority, and investigators were welcome to check over his assets.

It was his first address to the people in the two months since he stepped down. Shortly after, the prosecutor general issued a summons for Mubarak to appear for questioning.

Despite series of investigations into former top regime officials, relations between the military and protesters have soured over the last weeks. Protesters say the investigations were slow, and were outweighed by rights abuses by the new rulers.

Hundreds of protesters remain in military detention following a demonstration last month, while others have received swift trials before military courts.

A military tribunal slapped a three-year prison term on a blogger for charges of insulting the army and spreading false information, further antagonizing the protest movement.

State Department spokesman Mark Toner said the U.S. is "deeply concerned" about the conviction of Maikel Nabil Sanad.

Sanad, 26, carried reports of abuses by the military and accused it of remaining loyal to Mubarak.

Toner said Egypt was experiencing a "rocky time" in its transition from autocracy and called on Egyptian authorities to allow greater freedom of expression. This was not kind of progress the U.S. is looking for, he added.

Sanad's brother, Mark, said his family was denied the right to visit him Tuesday. His lawyer, Adel Ramadan, said the defense team is preparing to appeal the decision on procedural grounds before a supreme military court.

Maj. Gen. Ismail Etman told a private TV station Monday that Sanad's blog was not only insulting, but he also agitated against the country's policy of mandatory military conscription. He added that Sanad might have "foreign links," without elaborating.

Sanad, a conscientious objector, had also expressed pro-Israel sentiments, and recorded a video appealing to Israelis during the uprising to show solidarity with Egyptians.

________

Associated Press Writer Sarah El Deeb contributed to this report from Cairo.