poisoned Chicago lottery winner's body exhumed 18 January 2013 Last updated at 17:15 Authorities in Chicago have exhumed the body of a man who died of cyanide poisoning after winning the lottery. Investigators will perform a second autopsy on Urooj Khan in an inquiry into his death at 46. Khan died in July before he could collect the $425,000 (£267,000) payout. His death was initially attributed to natural causes. But after a concerned relative contacted authorities, tests showed he had been poisoned and police launched a homicide investigation. On Friday morning helicopters hovered over a cemetery as the exhumation got under way. Several trucks, police cars and a backhoe digger were seen at the grave site, the Chicago Tribune reported. 'Rule out' natural causes A spokeswoman for the Cook County medical examiner's office has said the autopsy will be performed immediately. Khan is due to be buried again on Monday. Authorities hope the forensic autopsy, which will include tests on his organs, will determine whether the cyanide was swallowed, inhaled or injected. Results are expected within two to three weeks. In court papers ahead of the exhumation, Chief Medical Examiner Stephen Cina said Khan's remains should be dug up as "expeditiously" as possible, since his body had not been embalmed. The autopsy was needed to "further confirm the results of the blood analysis as well as to rule out any other natural causes that might have contributed to or caused Mr Khan's death," Mr Cina argued in the court documents. The medical examiner's office first ruled Khan's death had been caused by a hardening of his arteries, but the case was reopened after a concerned relative suggested he may have been poisoned, prosecutors said. Further tests revealed lethal levels of cyanide in Khan's blood. Winning means everything Khan, who owned several dry cleaning stores, was named the lottery winner and presented with a giant cheque days after purchasing the winning ticket. "Winning the lottery means everything to me," he said on 26 June. Khan said that he would put some of his winnings into his business and donate money to a children's hospital. No motive has been established, but police say they have not ruled out the possibility that Khan was killed because of the lottery win. Khan is survived by his wife, Shabana Ansari, and a 17-year-old daughter from a previous marriage, Jasmeen. Mrs Ansari and Khan's father-in-law, Fareedun Ansari, have denied involvement in Khan's death.