Insurgents determined to wreck Iraq's constitutional referendum killed nearly 45 people and wounded dozens in a series of attacks Tuesday, including a suicide car bomb that ripped apart a crowded market in a town near the Syrian border, police said. US and Iraqi officials had repeatedly warned that the insurgents would step up their attacks to undermine Saturday's referendum, a crucial step in Iraq's democratic transition, and that appeared to be happening Tuesday. In the deadliest attack in Iraq in nearly two weeks, a suicide car bomb exploded at about 11 a.m. in a crowded open market in the northwestern town of Tal Afar, killing 30 Iraqis and wounding 45, said Brig. Najim Abdullah, Tal Afar's police chief. He said all the victims appeared to be civilians since no Iraqi or US forces were in the center of Tal Afar, which is 420 kilometers northwest of Baghdad. Insurgents also used two suicide car bombs, three roadside bombs and four drive-by shootings in the capital on Tuesday to kill a total of 14 Iraqis and wound 29, police said. The worst attack involved a suicide car bomb that exploded at about 12 noon at an Iraqi army checkpoint in a busy area of western Baghdad, killing eight Iraqi soldiers and one civilian, and wounding 12 soldiers, said police Capt. Qassim Hussein. The violence came four days ahead of Iraq's key vote on the new draft constitution, which Kurds and the majority Shiites largely support and the Sunni Arab minority rejects. Sunnis are campaigning to defeat the charter at the polls, though officials from all sides have been trying up to the last minute to decide on changes to the constitution to swing Sunni support. Many Sunnis fear the document would create nearly autonomous Kurdish and Shiite mini-states in the north and south, where Iraq's oil wealth is located, and leave most Sunnis isolated in central and western Iraq under a weak central government in Baghdad. Whether the constitution passes or fails, Iraq is due to hold elections for a new parliament on December 15. Across Iraq, militants are currently demanding that Iraqis boycott the referendum and have killed at least 384 people in the last 16 days in a series of attacks. In another development, a top Iraqi election official said Tuesday that Iraqi law will allow Saddam Hussein and thousands of other Iraqi detainees who have not been brought to trial to vote in this weekend's crucial constitutional referendum. However, Abdul Hussein Hindawi, one of the eight highest-ranking officials on the Independent Electoral Commission in Iraq, also said the organization was still awaiting a full list from the Interior Ministry and the US-led coalition of the detainees who should be allowed to receive copies of the draft constitution and to vote on Saturday at Abu Ghraib prison and several other US detention centers. "All non-convicted detainees have the right to vote. That includes Saddam and other former government officials. They will vote," Hindawi said in a telephone interview. Saddam's long-awaited trial is scheduled to begin October 19 on charges that he and seven of his regime's henchmen ordered the 1982 massacre of 143 people in a mainly Shiite town north of Baghdad following a failed attack on Saddam's life. More than 12,000 detainees are being held at the notorious Abu Ghraib prison, Camp Bucca and two other US military camps in Iraq, many awaiting trial or, in some cases, formal charges. Many of the detainees are believed to be Sunni Arabs who were rounded up by US and Iraqi forces on suspicion of supporting Sunni-led insurgent groups. Tal Afar, 150 kilometers east of the Syrian border, is located in an area where Iraq's Sunni-led insurgents have been active, making it difficult for coalition forces to maintain security in a large northwestern region of Iraq stretching to the Syrian border. On Sept. 28, a woman suicide bomber attacked an Iraqi army recruitment center in Tal Afar, killing at least six people and wounding 30. The woman, wearing men's clothing as a disguise, detonated her hidden explosives while standing in line with job applicants outside the center. That attack appeared to be carried out in retaliation for a major offensive by US and Iraqi forces that had routed insurgents in Tal Afar on Sept. 8-12. Iraqi authorities claimed that nearly 200 suspected militants were killed and 315 captured during the offensive. But when they completed the sweep, they discovered many of the insurgents had slipped out, some of them through a network of underground tunnels. In another development, Iraq has issued arrest warrants against the defense minister and 27 other officials from former Prime Minister Iyad Allawi's US-backed government over the alleged disappearance or misappropriation of $US1 billion in military procurement funds, officials said. Those accused include four other ministers from Allawi's government, which was replaced by an elected Cabinet led by Shiite parties in April, Ali al-Lami of Iraq's Integrity Commission said Monday. Many of the officials are believed to have left Iraq, including Hazem Shaalan, the former defense minister who moved to Jordan shortly after the new government was installed. For months, Iraqi investigators have been looking into allegations that millions of dollars were spent on overpriced deals for shoddy weapons and military hardware, apparently to launder cash, at a time when Iraq was battling a bloody insurgency that still persists. With strong US backing, Allawi was named head of the first transitional government after the US returned sovereignty to Iraq in June 2004, but his Iraqi List party did poorly in January parliamentary elections that swept the Shiite-Kurdish coalition into power. Besides Shaalan, warrants were issued against Allawi's labor, transportation, electricity and housing ministers, as well as 23 former Defense Ministry officials, said al-Lami, who heads Iraq's De-Baathification Commission, part of the Commission of Public Integrity. He did not name all the officials, and Shaalan and the ministers could not be reached for comment.