Updated

Despite leaflets calling for a "Day of Resistance" and a general strike to protest the U.S.-led occupation, Iraq was the picture of relative calm on Saturday. But in the north, a roadside bomb killed at least two U.S. soldiers in Mosul (search).

Though many skittish Baghdad parents kept their children home from school out of fear of terrorist attacks, most of the capital city's residents showed up for work Saturday and it was mainly business as usual.

L. Paul Bremer (search), head of the U.S.-led occupation, said Saddam loyalists — who also called for a three-day strike in the leaflets — had failed to rally Baghdadis around them.

"My understanding is there was a dropoff in schools but there was no general strike," Bremer told reporters. "Business was active and usual."

But in northern Iraq on Saturday,  two U.S. soldiers from the 101st Airborne Division (search) were killed and two wounded in the roadside bombing in Mosul, Iraq's third-largest city, according to the U.S. military. Iraqi police initially reported the explosion was a land mine.

Identities were withheld pending notification of relatives.

Iraqi police Lt. Walid Hashim said the men were inside two civilian cars when the blast occurred. Hashim said he rushed to the scene and saw that the drivers were dead and that the two passengers were both badly injured.

"I tried to pull one of the dead out but his leg was going to come off. They were cut all over by shrapnel [and] one was wounded in the abdomen and was moaning," Hashim said.

Insurgents were active elsewhere Saturday, attacking a U.S. convoy near Heet (search), 75 miles northwest of Baghdad, witnesses said. They said a man held up part of the wreckage from one vehicle and shouted, "with our blood and souls, we sacrifice for you, Saddam." U.S. military spokesmen had no confirmation of the attack.

Also Saturday, witnesses said an oil pipeline was on fire about 10 miles north of Saddam Hussein (search)'s hometown of Tikrit, an area of widespread opposition to the occupation. Witnesses said they suspected sabotage because the blaze was preceded by an explosion.

Sabotage to pipelines and the decayed state of Iraqi's infrastructure have slowed efforts to revive the country's giant oil industry, considered the key to rebuilding the nation's economy, which has suffered from more than a decade of wars and sanctions.

In Damascus, Syria, Iraq's neighbors opened a conference Saturday on the impact of the Iraq war. But the Iraqi interim government — insulted by a last-minute invitation — snubbed the talks and vowed to reject any decisions made there.

Iraqi officials had planned to use the forum to demand an end to cross-border infiltration by foreign fighters believed to have roles in a recent upsurge of violence in Iraq.

President Bush spoke about the violence in his weekly radio address.

"Some of the killers behind these attacks are loyalists of the Saddam regime who seek to regain power and who resent Iraq's new freedoms," Bush said. "Others are foreigners who have traveled to Iraq to spread fear and chaos and prevent the emergence of a successful democracy in the heart of the Middle East (search)."

The president said the attacks won't scare the U.S. away from Iraq.

"The United States will complete our work in Iraq," said Bush. "Leaving Iraq prematurely would only embolden the terrorists and increase the danger to America. We are determined to stay, to fight and to win."

Bremer told a Baghdad press conference that once the coalition gets additional money from Congress, it will accelerate the building of the new Iraqi army, police and other security forces.

"This is after all their country," Bremer said. "It is their future."

By September of next year more than 200,000 Iraqis will be involved in the defense of the country — either in the military, the police or the Civil Defense Force, a sort of national guard, according to Bremer.

"It will take time to root them out," Bremer told reporters, referring to the anti-American resistance in Iraq.

But his U.S. commander said it was still not known who exactly "they" are — who is financing and masterminding increasingly coordinated strikes. Those attacks spiked upward recently to an average of 33 a day, with most occurring in central Iraq.

"On who's financing and who's masterminding this whole thing, I can't give you any answers," said Lt. Gen. Ricardo Sanchez (search), Bremer's U.S. commander in Iraq.

Rumors had swept through Baghdad that bombings or other resistance action would strike the capital Saturday. A leaflet attributed to Saddam's ousted Baathist party declared Saturday a "Day of Resistance," and called for a three-day general strike.

Many shops in this city of five million people opened Saturday despite the resistance threat, but it appeared fewer Iraqis were willing to venture out in the morning. Traffic was noticeably lighter than usual, and merchants complained of fewer customers.

The impact on school attendance was more dramatic. Many parents kept their children at home Saturday, the first day of the Iraqi work week.

At one boys' secondary school, Al-Jawad, only 80 of 500 students showed up for class, deputy principal Abdel Karim al-Azzawi said. "Parents are worried about their children," al-Azzawi said.

Classes were canceled at the Al-Huda girls' elementary school after only 23 of 700 pupils arrived, according to the principal, Sana Naji Abbas. More than half the teachers also stayed home, she said.

One teenage girl who did set out from home Saturday morning sounded a defiant note. "We heard that they want to bomb schools, but we weren't afraid," said Sabrin Talib, 17. "I came to school today."

Merchants selling food reported no major drop in business, but others did.

"People can stop shopping but they cannot stop buying food and this is the reason why I was not affected today," said Amir Jawad, who runs the al-Zeytoun bakery in Baghdad's downtown Irkheita market.

However, Samir Saj, who owns a stationary and school material store, said there was very little business. And the owner of an electronics store, Assad Karim, said he had not sold any satellite dishes or electrical equipment all day. "Usually I should have sold several pieces by (midday)," he said.

Security was stepped up in the capital, and police checkpoints caused traffic jams. Many motorists were ordered to stop for inspections by policemen.

"I went out as usual and sent my children to school," Karima Dawth said. "Warnings by Baathists do not terrify us."

The "Day of Resistance" threat prompted some Western governments to issue warnings to their citizens in Baghdad. The Australian government warned of "a credible imminent threat" to the area around the Al Hamra Hotel in central Baghdad.

Foreign Ministry spokeswoman Lyndall Sachs, in Canberra, said staffers from the Australian government's mission in Baghdad have been "temporarily relocated to safer accommodations while we assess the threat further."

The U.S. State Department advised Americans to be vigilant.

The two deaths in Mosul bring to 122 the number of American soldiers killed by hostile fire since President Bush declared an end to hostile combat on May 1 when added to the total given by the Department of Defense (search) on Friday. A total of 114 U.S. soldiers were killed between the start of the war March 20 and the end of April.

Attacks against coalition forces escalated this week, starting with the Sunday missile barrage against the Al Rasheed Hotel in Baghdad. The following day, four near-simultaneous homicide bombings killed about three dozen people and injured about 200 in the capital, prompting the international Red Cross, the United Nations and other organizations to withdraw foreign staff.

U.S. officials have blamed former Baath Party figures, foreign fighters and Islamic extremists for the upsurge.

On Friday, The New York Times, citing unidentified senior U.S. officials, reported that Saddam himself might be playing a significant role in coordinating and directing attacks by his loyalists.

Bremer seemed to discount that report Saturday.

"We have no clear indication that Saddam himself is behind these attacks," he said. "There is some sign of control over these attacks at a regional level."

The Associated Press contributed to this report.