Egyptian President Hosni Mubarak has dismissed his cabinet and promised reforms as protests engulf his country.

In a televised speech broadcast early Saturday local time, Mubarak used his first public comments since the unrest began to defend the security crackdown on demonstrations.

"I assure you … I'm working for the people … as long as you're respecting the law," Mubarak said.

"We have to be careful of anything that would allow chaos," he said.

At the same, Mubarak tried to speak to the demonstrators who have filled Egypt's streets for days.

"I'll always be on the side of the poor," he said. "I am with bettering the economy."

Mubarak, who has ruled Egypt for three decades, has been facing the biggest pressure of his tenure amid protests that have gone on since Tuesday.

His nationally televised speech may have done little to placate those opposed to him.

"We want Mubarak to go and instead he is digging in further," said protester Kamal Mohammad. "He thinks it is calming down the situation, but he is just angering people more."

Before the president spoke, tens of thousands of anti-government protesters defied a night curfew and some reportedly set fire to Mubarak's party headquarters in Cairo. Flames were seen licking at the National Democratic Party headquarters shortly after 6 p.m. local time.

Next door to the party headquarters, the Egyptian army secured Cairo's famed antiquities museum early Saturday, protecting thousands of priceless artifacts, including the gold mask of King Tutankhamun, from looters.

The greatest threat to the Egyptian Museum, which draws millions of tourists a year, first appeared to come from the fire engulfing the ruling party headquarters.

Then dozens of would-be thieves started entering the grounds surrounding the museum, climbing over the metal fence or jumping inside from trees that line the sidewalk outside.

Suddenly young men — some armed with truncheons taken from the police — formed a human chain outside the main entrance in an attempt to protect the collection inside.

Finally, four armoured vehicles took up posts outside the building, and soldiers surrounded the museum and moved inside to protect mummies, monumental stone statues, ornate royal jewelry and other pharaonic artifacts.

The soldiers appeared to have rounded up all the would-be looters who made it onto the museum grounds.

Thousands of protesters also tried to storm the Foreign Ministry and state television buildings in Cairo.

With approximately 17 million people, Cairo is the most populous metropolitan area in Africa. Nearly half of the population is 19 or younger.

Egypt's military was deployed Friday for the first time. The military was called to help police enforce a curfew that began at 6 p.m. local time (11 a.m. ET.)

At least one report suggested, however, that some soldiers, many of them the same age as those leading the demonstrations, had removed their uniforms to take up with the protesters.

In Washington, U.S. President Barack Obama called on the Egyptian government to refrain from using violence against peaceful demonstrations, and urged authorities there to restore internet and cellphone services that have been cut off.

Obama said he spoke with Mubarak following the Egyptian leader's speech, and said he urged him to follow through on his pledges for a better democracy and more economic opportunities.

Obama said there must be "political, social and economic reforms that meet the aspiration of the Egyptian people."

An Egyptian soldier tries to calm anti-government protesters Friday night, several of whom had climbed atop his armoured personnel carrier near Tahrir Square in Cairo. (Lefteris Pitarakis/Associated Press)

"Violence will not address the grievances of the Egyptian people and suppressing ideas never succeeds in making them go away," he said.

Observers say the U.S. is sending a message to Egypt that it is closely monitoring the crisis and may review the $1.5 billion US in aid it sends to that country every year.

Canadians warned

Canadians are being warned to avoid Egypt's major cities unless it is absolutely necessary. The Department of Foreign Affairs said Canadians should not travel to Cairo, Alexandria or Suez.

The federal government also said Canadians currently in Egypt should avoid demonstrations and large gatherings. There are an estimated 6,500 Canadians in Egypt and all are believed to be safe.

In response to the widespread demonstrations and rioting, Egypt's national carrier, EgyptAir, suspended its flights from Cairo for 12 hours. The company said flights from abroad would be able to land, but departures were cancelled from 9 p.m. local time. A number of international airlines also cancelled flights to the capital, at least overnight.

The country's state TV said Mubarak ordered a curfew from 6 p.m. to 7 a.m. (11 a.m. to midnight ET) in Cairo, the Mediterranean port city of Alexandria and the flashpoint city of Suez, east of the capital. He expanded it nationwide shortly before 8 p.m.

He also ordered the army to collaborate with police to enact the order.

Television footage showed wounded protesters stumbling through the streets, bleeding and dazed with injuries to their heads, chests and legs.

Earlier reports that the country's leading pro-democracy advocate, Mohamed ElBaradei, was placed under house arrest could not be confirmed. ElBaradei is a Nobel laureate and former head of the UN's International Atomic Energy Agency.

ElBaradei's wife, Aida Elkachef, told CBC News her husband was at home, "safe" and "just resting." She said she did not know if he was under house arrest because he had not attempted to leave home since returning from protests earlier in the day.

"We saw that in the media as well," Elkachef said.

One person was killed in Friday's rioting. At least eight people have been killed in the protests since they began Tuesday.

"I can't believe our own police, our own government would keep beating up on us like this," said Cairo protester Ahmad Salah, 26.

Anti-government protesters threw stones and shouted at police during violent clashes in Cairo on Friday. (Goran Tomasevic/Reuters)

"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."

On Friday, clusters of riot police with helmets and shields were stationed around the city, at the entrances to bridges across the Nile and other key intersections.

"I've probably never seen so many riot police on the sides of the roads, dressed in black, carrying batons [and] masks," said CBC reporter Nahlah Ayed.

"The fact that special forces are being deployed today signals that [officials] are realizing this is far more serious than anything they have ever seen. The government here and the apparatus know that they have an angry crowd."

At their hotel in Cairo, Ayed and her cameraman were ordered to surrender their recording equipment; they refused.

ElBaradei supporters beaten

Police fired water cannons at ElBaradei and his supporters as they joined the latest wave of protests after noon prayers. They used batons to beat some of ElBaradei's supporters, who surrounded him to protect him.

A soaking wet ElBaradei was then reportedly trapped inside a mosque while hundreds of riot police laid siege to it, firing tear gas in the surrounding streets so no one could leave. Tear gas canisters set several cars ablaze outside the mosque, and several people fainted and suffered burns.

ElBaradei is "well-respected" in Egypt and "may offer a focal point" for the country's unrest, Ayed said.

But many Egyptians believe ElBaradei's return is premature and might not be enough to undo the strength of Mubarak's regime.

Internet, data services cut

Internet and cellphone data service was unavailable throughout the country, making it impossible for news of the protests to be broadcast via social networking sites like Facebook and Twitter.

Egyptian riot police with batons keep watch over thousands of protesters in downtown Cairo on Friday. (Lefteris Pitarakis/Associated Press)The lack of service made it virtually impossible for Egyptians, who use mobile phones almost exclusively, to communicate with one another.

Protest organizers had also been using social networking sites like Facebook and Twitter to spread information about the protests.

According to reports, the government ordered internet service providers to cut service early Friday morning.

Egypt's four primary internet providers — Link Egypt, Vodafone/Raya, Telecom Egypt, Etisalat Misr — all stopped moving data in and out of the country at 12:34 a.m., according to a network security firm monitoring the traffic. (The service provider Noor, which is used by the Egyptian stock exchange, remained active.)

An estimated one million people were expected to take part in the demonstrations Friday afternoon, which began following prayers at mosques in Cairo and elsewhere.

With files from The Associated Press