OTTAWA -- Prime Minister Jean Chrétien reached out to frightened Muslims yesterday, saying he is ashamed that many have been victims of ethnic slurs and hate attacks.

Speaking to about 500 Muslims gathered for prayers at an Ottawa mosque, Mr. Chrétien said that their faith, one of the world's great religions, has been unfairly smeared by the actions of the terrorists who attacked the United States last week.

"I have come here as your Prime Minister to bring a message of reassurance and tolerance."

He described the days since the attacks as a time of "great sadness and anxiety for Muslims across Canada because the cold-blooded killers who committed the atrocities in New York and Washington invoked the name and words of Islam as justification."

Mr. Chrétien's visit follows a televised address on Thursday night by U.S. President George W. Bush, who emphatically stated that Muslims should not be blamed for the recent attacks. The terrorist acts, he said, were carried out by "a fringe movement that perverts the peaceful teachings of Islam."

The public support comes as Muslims -- and other minority groups -- say they have been victims of an ugly backlash in the United States, Britain and Canada.

In Ottawa, the police hate-crimes unit is investigating an attack last Saturday night on a 15-year-old Muslim boy. He was swarmed and beaten unconscious by a gang of about a dozen youths.

Yesterday, an Ottawa Muslim, Abdullah -- he does not want his full name published -- said members of his family have stayed at home and out of sight since a playground incident last week.

Abdullah, who was on his way to prayers with his young son, said mothers had insulted his wife when she took their child out to play the day after the terrorist attacks. "We just stay in the house now," he said.

In counterpoint to the attacks and harassment, though, another trend is emerging. A spokeswoman for Indigo Books and Music, which encompasses about 200 Coles stores, 77 Chapters stores and 14 Indigo shops, said books on topics relating to conflicts in the Middle East, on Islam and on terrorism are sold out throughout the chain.

Bookstores have asked publishers for new editions on some of those topics now out of print. An example is a biography of Osama bin Laden.

"People are trying to make sense of this whole world," said Tracy Nesdoly, the Indigo spokeswoman. "People are searching for answers."

Mr. Chrétien, accompanied by Liberal, Canadian Alliance and New Democrat parliamentarians, said many Muslims have felt constrained when expressing sympathy and solidarity with the victims, even though many Muslims are counted among the missing.

Some Muslims have been singled out, denounced and attacked, he said. These acts "have no place in Canada or any civilized nation, and have made me feel shame as Prime Minister."

Mr. Chrétien's remarks were interrupted several times by the cry of approval, "God is great!"

Like all faiths, Islam is about peace, justice and harmony, he said. Noting that the government brought in legislation to provide stiffer penalties for hate crimes, Mr. Chrétien said he wants the police and courts to apply the full force of the law.

"I want to stand by your side to condemn the acts of intolerance and hatred . . . I turn my back on the people who have done this."

In his only public appearance of the day, Mr. Chrétien did not respond directly to Mr. Bush's call Thursday night for the world to join the United States in its fight against terrorism or be considered "with the terrorists."

Mohamed Elmasry, national president of the Canadian Islamic Congress, said in Toronto yesterday that the terrorists must be brought to justice, but the federal government must "reject the principle of kind-for-kind revenge."

Mr. Chrétien, who meets Mr. Bush Monday in Washington, has said previously that Canada will support the antiterrorist campaign with military forces if called upon.

Yesterday, he said Canada will not use the excuse of national security to abandon values of freedom and tolerance. "We will not fall into the trap of exclusion as we have in the past." Mr. Chrétien said all Canadians "stand together as one" against the evil of terrorism. "As one nation we defy the twisted philosophy of the terrorists, and shoulder to shoulder we will pursue the struggle for justice."

The Canadian Islamic Congress is asking mosques across the country to open their doors tomorrow, and for many Sundays to come, and invite the non-Muslim public in for cookies and tea. "This is not the time to hide out," Mr. Elmasry said.

But he said that some Muslims feel far too vulnerable to open the doors of their places of worship to people of different faiths. He said that incidents of harassment against Muslims and other visible minorities have soared to the "high hundreds," according to reports gathered by the country's Muslim associations.