TUNIS -- Facing public anger and internal divisions after the assassination of an opposition leader, Tunisia's largest Islamist party, which leads a governing coalition, blamed the news media, secular elites and the remnants of the old government for its troubles.
As Tunisians fretted about the specter of political violence, the party, Ennahda, did not seem to look inward. It strongly condemned the assassination, but did not see any blame for the anger in its own actions. But others did.
Its implacable critics renewed their charge that the killing was the result of Ennahda's conservative religious agenda. Others, including supporters of the group, said the movement's own missteps since coming to power contributed to the public outburst after the politician Chokri Belaid was gunned down last week. The group had lost confidence, some said, by focusing on power rather than on governing.
As tens of thousands took to the streets last week and Tunisia's divisions were laid bare, many waited to see how Ennahda would respond. Would it reach out to find common ground with some of its critics, or would it retreat to its base of support? The challenge resonates here and in Egypt, where the Muslim Brotherhood is facing even harsher questions about its rule.
Ennahda's leader, Rachid al-Ghannouchi, dismissed the criticism, saying that the movement remained popular and that a majority of Tunisians were not afraid of his group. "Just a tiny part of the aristocracy," he said.
Nevertheless, the anger amounted to a humbling setback for Ennahda, which had been in the vanguard of Islamists seeking political power after the Arab uprisings two years ago and had held up its record of building political consensus as a model. After decades of being jailed, or forced underground or into exile by authoritarian leaders, the Islamist groups' rise to power in Egypt and Tunisia has been swift. So has the reckoning on their rule.
"They thought that governing would be easy," said Abou Yaareb Marzouki, a philosophy professor who is close to Ennahda. "And they imagined that through governance, they will reject forced modernism," he said, referring to what he called a policy of westernization under colonial rulers and authoritarian governments. But Ennahda and the Brotherhood had swung too far in the opposite direction, he suggested, imposing "forced easternization."
Since the uprising against President Zine el-Abidine Ben Ali two years ago, Ennahda has insisted that whatever the results of elections, it would rule with others and had no intention of imposing a conservative religious agenda. After winning a plurality in Tunisia's first elections, the party formed a coalition with the center left.
Facing challenges that would test any government, the coalition became noted for its incompetence, failing to dent the economic crisis or reform institutions.
Ennahda was accused of coddling ultraconservatives, known as Salafis, some of whom have been tied to a string of violent episodes.
The blame intensified after the killing of Mr. Belaid, who had received death threats for his criticisms of Islamists. At his funeral on Friday, tens of thousands of mourners directed their anger at Ennahda and Mr. Ghannouchi, blaming them for fostering extremism and taunting the leader with an incendiary chant: "Slaughterer."
Intensifying the pressure on Ennahda, the prime minister, Hamadi Jebali -- a top Ennahda leader -- defied his colleagues by calling for the Islamist-led cabinet to replaced by technocrats with no political affiliations. Ennahda said it was still considering whether to accept the proposal to reconstitute the government, which many people believe could quiet some of the anger.
In an interview on Saturday, Mr. Ghannouchi said Tunisia's difficulties could be "contained," saying he was not worried that the country would devolve into violence. "The Tunisian people are known for being peaceful," he said.
He said he was surprised at the accusations against Ennahda, which understood that its success in governing depended on stability. "These kinds of things happen in revolutions," he said, speaking of the assassination. He avoided Mr. Belaid's funeral to "avoid tensions," he said, but was clearly stung by the chants against him, which he called part of a demonization campaign.
Mr. Ghannouchi said the party remained "open and accepting," and said most people were not preoccupied with ideological conflict but with concerns like food and medicine. He blamed a "French model of secularism" for conflicts in Tunisia, and insisted that no more than 20 percent of Tunisians were opposed to Islamist rule. "The rest are against radical secularism," he said.
Khalil al-Anani, a scholar of Middle East Studies at Durham University in England, said the Islamists shared a misconception that by securing electoral victories, they were free to act as they wished. "They replicate the policies of authoritarian regimes, and underestimate the weight of secular and liberal forces." And they did not understand how the uprisings had changed the structures of power. "No one can claim the authority of the street in the Arab world," he said.
Abdulbasset Belhassan, the president of the Tunis-based Arab Institute for Human Rights, said the Islamists "are facing a strategic choice -- between keeping an ideological approach based on their old legacy, or entering a new era based on human rights and democracy." "They should take a historical decision," he said. "The revolution was not made by one party."
Farah Samti contributed reporting.
Correction: February 12, 2013, Tuesday
This article has been revised to reflect the following correction: An earlier version of the caption for the picture with this article referred incorrectly to the demonstrators. They were rallying in support of Ennahda, not against it.
This article originally appeared in The New York Times.