according to the Associated Press:

An autopsy on Heath Ledger was inclusive, and more tests are needed, the medical examiner's office said Wednesday, a day after the 28-year-old actor was found dead with sleeping pills nearby.

It will take about 10 days to complete the investigation, said Ellen Borakove, a spokeswoman for the medical examiner.

Earlier, police said the death was caused by a possible drug overdose and appeared to be accidental.

Fans left flowers and candles Wednesday outside the apartment building in Manhattan's SoHo where the body of the Oscar-nominated star of "Brokeback Mountain" was found.