Iraqi soldiers arrested a wanted terrorist who tried to sneak through a checkpoint in Baghdad dressed as a bride, complete with a fake bridegroom and witnesses. The man — in a white bridal gown with a veil over his face — was caught when soldiers became suspicious, because all the members of the wedding party were men, and lifted his veil.

With tens of thousands of extra American troops in the capital, and a growing number of local, US-backed militia guarding neighbourhoods, insurgents are using elaborate disguises to move around. Three weeks ago Iraqi security forces at a different roadblock in Baghdad found two men, who were wanted, being transported in coffins. A suicide bomber, dressed as a shepherd, killed nine policemen when he blew himself up at a police checkpoint in Baqubah, north of Baghdad, yesterday, after herding a flock of sheep towards it.

The influx of US troops has helped to reduce daily violence in Baghdad, but it has also led to an increase in shootings of civilians that have, in the past, alienated the local population from the American Army.

US forces killed at least six Iraqi civilians in separate incidents yesterday, including three women and a child, who died after troops shot at a minibus taking bank employees to work in Shaab, a violent district of Baghdad. A spokesman for the American military said that the troops opened fire when the driver failed to stop after a warning shot was fired.

“The bus was travelling on a street that is off-limits to vehicles other than passenger cars,” the spokesman said.

US troops, in an operation targeting al-Qaeda, also shot at a car that was said to have ignored warnings to stop in Baiji, 140 miles (225km) north of Baghdad. Iraqis have often complained that signals from US troops are difficult to understand, or that the camouflaged soldiers are not always clearly visible.

In spite of the renewed violence the first convoy of about 12 buses carrying Iraqi exiles was reported to have left Damascus for Baghdad yesterday, a day later than planned. The Iraqi Government thinks that the security situation has improved enough for the 1.3 million Iraqis sheltering in Syria to return home.

The United Nations has expressed serious concern that Baghdad remains volatile and that many people who return may find themselves without a job and at risk from sectarian violence.

Officials from the Iraqi Embassy in Damascus estimated that the buses were carrying 700 people, including many children. They were expected to arrive at the Syrian-Iraqi border under the cover of darkness, and then walk to a set of Iraqi buses sent from Baghdad for the rest of the journey.

The Iraqi Embassy expects to put on many more buses to ferry more of the 1.5 million refugees home. One official said: “The first convoy is a test. We are sure all will go well, God willing.”

The UN High Commissioner for Refugees (UNHCR) has appointed a team to travel to Baghdad to oversee the returns. He said that many people were heading home only because they had run out of money or because Syria has started to impose tough visa restrictions about working on the Iraqis who have fled there in recent years.

The commission said that it did not believe that the time had come “to promote, organise or encourage returns of refugees and displaced persons”. Syrian border officials report that as many as 1,000 people are returning every day.

Despite the warnings, many Iraqis in Damascus were preparing for the trip. “I hear it’s better now in Baghdad,” Yassar Malas said. “You can walk around again and shops are open. Maybe they even have jobs — not like here where I can’t work. I am homesick as well.”

Some Iraqis are still wary that, despite a recent drop in violence, the potential for a return to sectarian warfare and death squads still haunts Iraq. “I will not gamble, not with the lives of my children,” Yusef, 38, a refugee, said. “We have waited here two years, we can wait another two months.”

Times Recommends

• Should Knox’s trial even have reached the courtroom?
• 'Was it real?' The US bailout nightmare
• Iranian opposition plays the long game