LOS ANGELES (AP) — A detective testified Monday that the doctor charged in the death of Michael Jackson told police he had given the singer a powerful anesthetic at least six nights a week for two months before he died.

Dr. Conrad Murray also acknowledged giving propofol to Jackson about 10:40 a.m. on the morning he died and said he only left Jackson alone for two minutes before returning to find the singer not breathing, Los Angeles police detective Orlando Martinez testified.

Murray also told police he had given Jackson several sedatives intravenously earlier in the day, Martinez said.

Phone records show paramedics were not called until 12:21 p.m., and prosecutors contend the singer was dead before help arrived.

Deputy District Attorney David Walgren asked the detective whether the doctor explained why he didn't immediately call 911.

He said he was caring for his patient and he did not want to neglect him," Martinez said.

Murray has pleaded not guilty to involuntary manslaughter. Prosecutors contend he administered a lethal mix of propofol and other sedatives to the singer.

Martinez said Murray reported giving the pop star 25 milligrams of the anesthetic — about half the usual dose.

Murray told police Jackson had been complaining about not being able to sleep and said he might have to cancel his series of planned London comeback concerts.

Earlier testimony by a pharmacist showed Murray purchased 255 vials of propofol during the three months before the singer died.

Murray bought 130 vials of propofol in 100-milliliter doses and another 125 vials in the smaller dose of 20 milliliters, said Tim Lopez, owner of Applied Pharmacy Services in Las Vegas, where Murray has a clinic.

Lopez took the witness stand during the fifth day of a preliminary hearing to determine if there is enough evidence for Murray, who was Jackson's personal physician, to stand trial.

The four shipments of propofol were purchased between April 6 and June 10, 2009, with most of the drugs shipped to the Santa Monica home of Murray's girlfriend, testimony showed. Jackson died on June 25.

Murray also purchased sedatives known as benzodiazpines, Lopez testified.

Lopez said he was first contacted by Murray in November 2008 for information about buying Benoquin, a depigmentation cream used to treat the skin disease vitiligo. Jackson was known to suffer from the ailment, but Lopez said Murray told him he had many African-American patients suffering from the disorder.

Lopez said he and Murray lost touch until late March, 2009, when Murray called back and ordered a large amount of the cream. Lopez said he checked Murray's credentials and had his courier deliver the order to Murray's Las Vegas clinic.

On April 3, Lopez said, Murray called back to say he was happy with the cream and wanted to place another order.

He specifically asked about propofol and saline bags," Lopez said, recalling that he told Murray he could handle his request.

Murray never disclosed who would receive the drugs, Lopez said.

Murray has told police he was concerned Jackson was addicted to propofol, and that he was trying to wean the singer from it. A dozen vials of propofol were found in Jackson's bedroom after his death.

Dr. Zeev Kain, anesthesiology department chair at the University of California, Irvine Medical Center, has said three 100-milliliter vials of propofol normally used in surgery would be enough to keep a patient unconscious for several hours.

A doctor should not use propofol at home to start with," Kain said.

In other testimony, a retired federal investigator said he had retrieved -mail from Murray's cell phone containing an exchange between the doctor and a London insurance broker handling a policy for Jackson's planned series of comeback concerts.

The broker asked Murray on the morning of Jackson's death to address press reports that Jackson was in poor health.

As far as the statements of his health published by the press, let me say they're all felitious (sic) to the best of my knowledge," Murray replied in an e-mail.

Using phone records and testimony from police and Murray's current and former girlfriends, prosecutors tried to show Murray was on the phone throughout the morning of Jackson's death, even after administering propofol to the singer.

They hope to convince a judge of several key points: that Murray was distracted when he should have been monitoring Jackson, that he delayed calling 911, that he botched CPR efforts and that the singer was dead before help was summoned.

Defense attorneys rarely present witnesses or their own theories during preliminary hearings. In Murray's case, they did not make an opening statement and have only hinted at potential arguments as they questioned witnesses.

Murray could face up to four years in prison if tried and convicted.