US forces killed some 70 insurgents in western Iraq on Monday after a majority of voters in six Iraqi provinces said "Yes" to a new constitution in Saturday's landmark referendum.

US forces launched an air strike on a group of suspected insurgents who were attempting to plant a roadside bomb in the western city of Ramadi, about 100 km west of Baghdad, a US military statement said, adding that 20 men were killed on the ground.

However, several witnesses and a local tribal leader said the people killed were civilians who had gathered there to see the wreckage of a US military vehicle.

Another 50 militants were killed in separate clashes and air strikes around Ramadi, according to the statement. But witnesses said at least 14 among the 50 were civilians.

Ramadi has long been an insurgent bastion in the mainly Sunni western Anbar province.

The killing came two days after Iraqis voted on the draft constitution in the referendum, which witnessed a large turnout of Sunni Arabs, who had been virtually marginalized in the country's political process after shunning the Jan. 30 parliamentary elections.

Initial counting showed on Monday that more than 90 percent of voters in six Iraqi provinces said "Yes" to the constitution in Saturday's referendum.

"More than 90 percent voters in six provinces said 'Yes' to the constitution. They are Basra, Karbala, Misan, Najaf, Dhi Qar and Wasit," an electoral official was quoted by the National Iraqi News Agency (NINA) as saying.

However, the Sunni-dominant Salahudin province was obviously against the charter with more than 80 percent of its voters saying "No", according to NINA.

Official results are expected next week.

US President George W. Bush has been optimistic about the approval of the constitution, saying Iraq's Sunnis sent a hopeful signal by voting in large numbers in the referendum.

"My first reaction to the vote was that an increase in turnout was an indication that the Iraqi people are strongly in favor of settling disputes in a peaceful way," Bush told reporters after meeting with Bulgarian President Georgi Purvanov on Monday.

"I was pleased to see that the Sunnis have participated in the process. The idea of deciding to go into a ballot box is a positive development," he said.

The president has hailed Saturday's referendum on the draft constitution as a "positive day for the Iraqis and as well for world peace".

On the same day, UN Secretary-General Kofi Annan praised the bravery of the Iraqi people for voting in Saturday's constitutional referendum but warned that violence in the country may not ease automatically after the completion of the constitutional process.

"The Iraqi population showed incredible courage, going to vote in large numbers despite the security situation on the ground," Annan told reporters at the UN headquarters in New York.

Asked whether the referendum would help reduce violence in Iraq, he said it would be difficult to predict what would happen after the votes are counted. "I don't think we can legitimately expect that, given the facts and what we know," he said.

"But at least, they have chosen to use ballots and not bullets, and I hope this is a lesson that will augur well in the future," he added.

Annan said the United Nations stands ready to help as Iraq prepares for national elections in December. "We will continue to assist them if they so desire," he said.

Source: Xinhua