U.S. aircraft blasted the rebel stronghold of Falluja for a third time in 24 hours in a concerted effort to hit militants loyal to guerrilla chief Abu Musab al-Zarqawi, Washington's number one enemy in Iraq. The strike came just before U.S. Secretary of State Colin Powell said the insurgency in Iraq was worsening, but the United States was taking action to improve security ahead of elections in January. "We are fighting an intense insurgency," Powell said on Sunday on ABC's "This Week" programme. "Yes it's getting worse and the reason it's getting worse is that they are determined to disrupt the election. "And because it's getting worse we will have to increase our efforts to defeat it, not walk away and pray and hope for something else to happen," Powell said. He also told CNN's "Late Edition" that the United States was helping interim Iraqi Prime Minister Iyad Allawi organise a conference of Middle Eastern and Western countries this year to discuss how neighbouring states can help Iraq. The meeting may be held in October or early November, possibly in Amman, Jordan, or Cairo, Egypt, Powell said. The air strike was aimed at about 10 suspected militants meeting in the city centre to plan operations, the U.S. military said. Eight people were killed and 17 wounded, Anas Ahmed, a doctor at a nearby hospital, said. The latest in what the military calls "precision strikes" raised the death toll for the series to 15 killed and 30 wounded, among them women and children, doctors said.