Heroin recovered at Oscar-winning actor Philip Seymour Hoffman's flat after he was found there dead with a syringe in his arm has tested negative for the powerful additive fentanyl.
Samples taken from Hoffman's Manhattan New York flat did not contain the potent synthetic morphine, which is added to intensify the high and has been linked to 22 suspected overdose deaths in western Pennsylvania, a police official said.
Investigators also have discovered that the Capote star made six ATM transactions for a total of 1,200 dollars (£735) inside a supermarket near his home the day before his death.
They have been piecing together his final hours using video surveillance to determine his whereabouts.
The 46-year-old actor was found dead in the bathroom of his Manhattan flat on Sunday. His door was double-locked when his body was discovered around 11.30am local time by his assistant and a friend.
Besides the bank records, investigators discovered buprenorphine, a drug used to treat heroin addiction, at Hoffman's flat and are examining a computer and two iPads found at the scene for clues.
A spokeswoman for the medical examiner's office said yesterday there has been no official determination made on what killed Hoffman.
Police have said the medical examiner's ruling on his cause of death will determine whether there is any criminality but they suspect it was an overdose.
More than 50 small plastic envelopes of heroin were recovered in Hoffman's apartment along with syringes, a charred spoon and various prescription medications, including a blood pressure drug and a muscle relaxant.
Some of the packets were variously stamped with the ace of hearts and others with the ace of spades.
The New York Police Department's intensive effort to discover the source of the drugs in an apparent accidental overdose is unusual.
Courts have found in past rulings that under state law drug dealers cannot be held liable for a customer's death.
Addiction specialist Dr Louis Baxter, a former president of the American Society of Addiction Medicine, said that addicts, especially those who have built up high tolerances, can use as much as two bundles of heroin, or about two dozen packets, per day.
"Addicts with financial means will actually stockpile their drug," he said. "Someone who has developed tolerance, who is seeking to develop a high, may need to inject every two hours or so."
It said Hoffman's family had requested a private funeral, which will be held on Friday.