Iraq's prime minister put his nation on its highest level of alert for terror attacks, warning of plots to sow fear and chaos as the US combat mission in the country formally ends Tuesday. The Iraqi security forces who will be left in charge of guarding the nation have been hammered by near-daily bomb attacks, prompting criticism of the government's readiness for the American troop drawdown. Prime Minister Nuri Al-Maliki said Friday that Iraqi intelligence indicated an Al-Qaeda front group and members of Saddam Hussein's outlawed Baath party are collaborating to launch attacks “to create fear and chaos and kill more innocents.” “We direct the Iraqi forces, police and army and other security forces, to take the highest alert and precautionary measures to foil this criminal planning,” Al-Maliki said in a statement to state-run television. A senior Iraqi intelligence official said security forces believe suicide bombers have entered the country with plans to strike unspecified targets in Baghdad by month's end. President Barack Obama, meanwhile, used his weekly radio address to reaffirm his campaign promise to end the war in Iraq and refocus on Afghanistan as home to the top threats against America. “The bottom line is this: the war is ending,” Obama said from the Massachusetts island retreat of Martha's Vineyard, where he was on vacation. “Like any sovereign, independent nation, Iraq is free to chart its own course.” “In the months ahead, our troops will continue to support and train Iraqi forces, partner with Iraqis in counterterrorism missions and protect our civilian and military efforts,” Obama said. And by the end of next year, all of our troops will be home.” Al-Maliki said insurgents would try to exploit widespread frustration with years of frequent power outages and problems with other public services by staging riots and attacks on government offices. “They will also work on taking advantage of some of the crises of services ... to spread chaos,” he said. Hours after his remarks, the Al-Qaeda-linked militants claimed responsibility for more than two dozen bombings and shootings across the nation this week that killed 56 people – more than half of them Iraqi soldiers and policemen. In a statement posted on a militant website Saturday, the group said the coordinated attacks targeted the “headquarters and centers and security barriers for the army and the apostate police.” Under a security agreement between Washington and Baghdad, all US troops are to be out of Iraq by the end of 2011. The prime minister seemed to recognize that security forces alone would not be able to stop the attacks, and he appealed to citizens to be vigilant. “We call on the nation to have open eyes to monitor the movements of those terrorists and keep such criminal gangs from halting the progress of our nation.”