The county sheriff investigating the death of Prince is asking for help from the Drug Enforcement Administration, federal law enforcement officials told NBC News on Wednesday.
The officials say prescription painkillers were found in his possession when he died and in his house near Minnesota, though officials have yet to say what role, if any, those medications may have played in his death.
An autopsy was conducted last week, but the medical examiner said it would take weeks before the cause of death would be disclosed.
The DEA's role, officials say, will be to determine such things as where the medications came from, and what prescriptions Prince had obtained. DEA agents often check those records in death investigations.
Some of his friends have said he took the painkiller Percocet to relieve pain in his hips — the result of years of jumping during performances.
See Prince through the years: