A Tunisia-style uprising is unlikely to take place in Morocco in the medium term, Fitch Ratings said on Thursday.

In an analysts' call on North Africa, Fitch said heavy investment in infrastructure and progress in alleviating poverty, as well as relative political openness, mitigated the danger of contagion from Tunisia.

Activists trying to oust Egyptian President Hosni Mubarak set fire to buildings in the eastern city of Suez overnight and played cat-and-mouse with police on a third day of protests against his 30-year rule.

Prominent reform campaigner Mohamed ElBaradei said from Vienna shortly before his return to Egypt to join in demonstrations that it was time for Mubarak to step aside.

"He has served the country for 30 years and it is about time for him to retire," ElBaradei, the Nobel Peace Prize-winning former head of the U.N. nuclear watchdog, told Reuters.

"Tomorrow is going to be, I think, a major demonstration all over Egypt and I will be there with them."

Egyptians torched a police post in Suez early on Thursday in response to the killing of three demonstrators earlier in the week, a Reuters witness said. Police fled the post before the protesters burned it using petrol bombs.

On Wednesday evening, people in Suez had set a government building and another police post on fire and tried to burn down a local office of Egypt's ruling party.

Those fires were all put out before they engulfed the buildings but dozens more protesters gathered in front of the partially burned police post later on Thursday morning.

ElBaradei's arrival could spur protesters who have no figurehead, although many activists resent his absences in recent months.

The anti-government protests, unprecedented during Mubarak's rule of a state that is a key US ally, have seen police fire rubber bullets and tear gas at demonstrators throwing rocks and petrol bombs.

One policeman has been killed in Cairo in the clashes, which erupted on Tuesday, inspired by a popular revolt in Tunisia.

Thousands of protesters also took to the streets in Yemen on Thursday to demand a change of government there.

Protesters in all three countries complain about surging prices, a lack of jobs and authoritarian rule that has relied on heavy-handed security to keep dissenting voices quiet.

Al-Arabiya television said on Thursday Egypt's general prosecutor had charged 40 protesters with trying to "overthrow the regime".

And today it was announced that members of Tunisia's former regime ousted by popular street protests are not welcome in Canada.

That's according to the country's Prime Minister Stephen Harper in Rabat on Thursday.