Hosni Mubarak, the besieged president of Egypt, said in a televised speech he would dissolve his government but stay in power, as thousands of protesters defied a government-ordered curfew in a direct challenge to his three-decades-long rule.

In his first public appearance since the mass protests began on Tuesday, the 82-year-old leader pledged to pass wide-ranging reforms. He also said he had asked the government to resign and would appoint a new one in its place.

"The incidents that took place today and the past few days have left the majority of the Egyptian people fearing for Egypt and its future," he said in Arabic. "I will take all steps to maintain the safety and security of all Egyptians."

Mubarak's address came hours after the national government imposed a curfew in an attempt to quell escalating mass protests. The Egyptian military fanned out across Cairo after sunset Friday in an attempt to enforce the curfew but the demonstrations continued into the night.

On the streets of the capital, news of the president's TV appearance led to new chants of "Down, down Mubarak!"

Thousands of demonstrators attempted to storm the state TV building and the Foreign Ministry, while other protesters simply held their evening prayers outdoors.

There were pitched battles against police with protesters throwing stones and firebombs, torching tires, police cars and the ruling party's headquarters. Video footage and still images showed smoke rising across Cairo and several other cities.

EgyptAir, the national carrier, also suspended flights to the capital for 12 hours.

Earlier in the day, there were reports of several policemen in the Egyptian capital stripping their uniforms to join the ranks of protesters. An Associated Press correspondent reported seeing demonstrators cheering the defectors and hoisting them on their shoulders.

Friday's protests spread to nearly half of Egypt's provinces. At least eight people have been killed in the unrest, with hundreds reportedly injured.

"I can't believe our own police, our own government would keep beating up on us like this," 26-year-old protester Ahmad Salah told The Associated Press in Cairo.

"I've been here for hours and gassed and keep going forward, and they keep gassing us, and I will keep going forward. This is a cowardly government and it has to fall. We're going to make sure of it."

Demonstrators are angry with a regime that's largely seen as corrupt, oppressive and unresponsive to the poverty that afflicts many of the country's 80 million residents.

American reaction

U.S. President Barack Obama said he advised Mubarak that he has a responsibility to make his country more democratic and increase economic opportunity, as he pledged to in his televised speech.

"Violence will not address the grievances of the Egyptian people and suppressing ideas never succeeds in making them go away," Obama said in Washington. "What's needed now are concrete steps that address the rights of the Egyptian people."

Mubarak has long been considered among America's closest allies in the region. But due to the week's events, a White House official said Washington would review its aid policy on Egypt -- which has been one of the largest recipients of American aid for years.

The most violent clashes were reported in the eastern city of Suez, where protesters seized weapons from a police station before burning it down and destroying more than two dozen police trucks parked nearby.

One demonstrator was reported killed in a gunbattle that erupted when the mob tried storming a second police station. A female demonstrator was also reported killed in Cairo, bringing the number killed in the last four days of protest to nine.

The anti-government protests raged across Egypt despite an official ban on public demonstrations, a heavily-armed police presence and an overnight communications shutdown.

Leaders and supporters of the country's largest opposition group Muslim Brotherhood also disappeared in a wave of arrests overnight. But the crackdown did little to quiet protesters' dissatisfaction with rampant unemployment and rising food prices in the North African nation.

Imams had been instructed to tell their followers not to take to the streets after prayers on Friday, but crowds still left ready to join the chorus calling for the end of Egyptian President Hosni Mubarak's 30-year rule.

House arrest

Just-returned Nobel laureate Mohamed ElBaradei was among the protesters who poured out of one mosque in Cairo Friday, chanting "down, down Hosni Mubarak."

However, when he and his supporters tried to take to the streets following noon prayers they were beaten back by police wielding water cannons and tear gas. ElBaradei, who is also the former head of the UN nuclear watchdog, was subsequently placed under house arrest.

Elsewhere in the Egyptian capital, police reportedly used rubber bullets to subdue the crowds.

Foreign correspondent Martin Seemungal said from Cairo that police tried using strong tactics to quell the demonstrations before they can gain momentum.

"When the demonstrators try to gather -- the biggest I saw was a group of about 400 -- they approached the police line, the police then charged them, fired tear gas and drove them away fairly quickly," Seemungal told CTV's Canada AM.

Not far away, Seemungal said, pedestrians and traffic in the city of 18 million appeared to be going about life as usual as security forces attempted to keep protesters away from the rest of the city's residents.

Groups of protesters, some numbering in the tens of thousands, they were met by clusters of security forces stationed at the entrances to bridges across the Nile and other key intersections.

There were also reports of protests in Asyut and Minya south of Cairo, as well as al-Arish in the Sinai Peninsula. Local TV stations also reported clashes between demonstrators and police in the Mediterranean port city of Alexandria.

Seemungal said Internet access ceased at approximately 1 a.m. local time Friday morning, followed by the data service to smartphones about one hour later.

"The only way to get messages out of Egypt now is by independent satellite or by landline," he said.

Egyptians outside the country have been updating social media websites with information gleaned from voice calls with those inside Egypt.

In a statement released Thursday night, Minister of Foreign Affair Lawrence Cannon echoed Obama's call for peaceful avenues for political expression.

"We urge all parties to refrain from violence, and, in particular, we urge the Egyptian authorities to respond to these protests peacefully," Cannon said. "We call on the Government of Egypt to ensure that freedom of expression is respected by, among other measures, unblocking Internet sites."

A Facebook page run by the anti-Mubarak protesters includes a call for new elections, the release of prisoners being held without charge or trial and a pledge the president will not seek another term.

With files from The Associated Press