Several weeks after his untimely death on May 24, the Associated Press reports that ex-Wilco member Jay Bennett (45) died of an overdose. An autopsy revealed toxic amounts of the painkiller fentanyl, according to the Champaign County Coroner's office. Authorities are treating his death as an accident.

Fentanyl is prescribed by doctors to treat chronic pain -- something that Bennett suffered from to the point that, in the weeks leading up to his death, he had become focused on raising enough funds to undergo hip surgery as he was experiencing debilitating pain from a decade-old hip injury. (Like many musicians, Bennett did not have health insurance.) Fentanyl is applied via patches and is considered more potent than morphine.

Tragic as it is, the overdose also has some sense of irony -- after he acrimoniously parted ways with Wilco in 2001, his former bandmate Jeff Tweedy checked into rehab to battle his own addiction to a painkiller (in his case, Vicodin, which he was originally prescribed for migraines).

Bennett had recently filed a lawsuit against Tweedy for what he claimed were unpaid royalties from his seven years with Wilco.