TORONTO – A day after Canada’s newspapers carried front-page photos of the flag-draped coffins of four soldiers killed in Afghanistan, the Conservative government slapped a ban on press coverage of the coffins’ return home to Canada yesterday.

The order, and an earlier decision by the government not to lower the national flag to half-staff to mark the soldiers’ deaths, brought criticisms that Prime Minister Harper is trying to muffle reaction to Afghanistan casualties.

“What is the prime minister trying to hide by dishonoring fallen soldiers?” the leader of the opposition New Democratic Party, Jack Layton, demanded in the House of Commons yesterday.

“We should not be trying to hide these things,” the leader of the Liberal Party, Bill Graham, echoed.

Mr. Harper insisted the government is protecting the privacy of grieving families, and Conservative officials said the flag has traditionally not been lowered for war casualties. But the debate underlined the public’s qualms over Canada’s beefed-up role in Afghanistan, and the government’s nervousness about uncertain support for that operation.

Canada now has 2,300 troops in Afghanistan, and has recently moved its operation from Kabul to the more dangerous Kandahar region in the south. The four soldiers, killed Saturday in a roadside bomb blast north of Kandahar city, brought the Canadian death toll in Afghanistan to 16, including a diplomat. The country’s papers were filled with stories about the four fallen men. The attack was the deadliest by insurgents against Canadian troops since they deployed to Afghanistan.

Mr. Harper, who took office in January, is a strong supporter of the military mission. But the most recent public opinion poll found Canadians evenly split on having troops in Afghanistan.

The redeployment to Kandahar and the casualties have led to “a series of rude awakenings for Canadians,” the executive director of the Dominion Institute, which runs a veterans’ awareness project, Rudyard Griffiths, said. That unease is increased by Canadians’ strong opposition to the American-led invasion of Iraq and to the Bush administration, he said.

“It’s a very fine balancing act the prime minister has to manage, communicating to Canadians that Afghanistan is not Iraq,” Mr. Griffiths said. As reports of Afghan civilian and Canadian military casualties mount, “it’s going to transfer that negative image of a bungled enterprise, of hopelessness, from George Bush to Stephen Harper.”

The comparison came quickly yesterday after the government ordered journalists away from the Trenton, Ontario, air base when the coffins of the four soldiers arrived.