A backhoe is seen at Rosehill Cemetery in Chicago, Friday, Jan. 18, 2013, as workers begin the process of exhuming the body of Urooj Khan who was poisoned with cyanide after winning the lottery. Khan died in July as he was about to collect $425,000 in lottery winnings. His death was initially ruled a result of natural causes, but a relative pressed for a deeper look and his death was reclassified as a homicide. Workers at Rosehill Cemetery in Chicago on Friday, Jan. 18, 2013, begin the process of exhuming the body of Urooj Khan who was poisoned with cyanide after winning the lottery. CHICAGO (AP) - The body of a Chicago man who was poisoned with cyanide after winning the lottery was exhumed Friday for another autopsy that authorities hope will help solve the mystery surrounding his death. A black hearse escorted by four police cars carried away the body of Urooj Khan from a cemetery on the city's North Side shortly after 9 a.m., and the Cook County Medical Examiner's Office was expected to perform the autopsy immediately, spokeswoman Mary Paleologos said. She said examiners will take blood, tissue, bone, hair and nail samples. They'll also examine the lungs, liver, spleen and contents of the stomach and intestines. Paleologos said tests on Khan's organs also may determine whether the poison was swallowed, inhaled or injected. The autopsy was expected to be finished by Friday afternoon, though it will take two to three weeks to get test results, she said. Khan, 46, died in July as he was about to collect $425,000 in lottery winnings. His death initially was ruled a result of natural causes. But a relative asked for further tests, which revealed he was poisoned. Khan's wife, Shaana Ansari, and other relatives have denied any role in his death and expressed a desire to learn the truth. Authorities remain tightlipped about whom they may suspect. Khan had come to the U.S. from his home in Hyderabad, India, in 1989, setting up several dry-cleaning businesses and buying into some real-estate investments. Despite having foresworn gambling after a pilgrimage to Mecca in 2010, Khan bought a ticket in June. He jumped "two feet in the air" and shouted, "I hit a million," he recalled at a lottery ceremony later that month. He said winning the lottery meant everything to him and that he planned to use his winnings to pay off mortgages, expand his business and donate to St. Jude's Children's Research Hospital. He was just days from receiving his winnings when he died before dawn on July 20. The night before, Khan ate dinner with his wife, daughter and father-in-law in their house in Chicago's North Side neighborhood of West Rogers Park, home to many immigrants from India and Pakistan. Sometime that night, Khan awoke feeling ill and collapsed as he tried to get up from a chair, his wife has said, according to the Chicago Sun-Times. With no outward sign of trauma, authorities initially determined Khan had died of natural causes. But a concerned relative - whose identity remains a mystery - came forward with suspicions and asked authorities to take a closer look. Further toxicology tests found a lethal amount of cyanide in his blood, leading the medical examiner in November to reclassify the death a homicide. Khan died without a will, opening the door to a court battle. The businessman's widow and siblings fought for months over his estate, including the lottery check.