Michael Jackson was killed with a lethal dose of anaesthetic by his personal physician Dr Conrad Murray, a jury has decided at the doctor"s trial in Los Angeles.

Following a six-week case, cardiologist Dr Conrad Murray, 58, was convicted of involuntary manslaughter after the jury decided his treatment of the singer had been criminally negligent.

Murray, who will lose his medical licence, sat stone-faced as the unanimous verdict was delivered.

He was handcuffed and remanded in custody for sentencing on Nov 29. He faces a maximum sentence of up to four years in prison.

In court, members of the late singer’s family shouted “Yes” as the verdict came down. Jackson’s mother Katherine sobbed quietly. Later, outside court, she said: “I feel better now.”

As Murray, wearing a light grey suit, was led out of the courtroom in handcuffs he cast a final glance at his own mother, who whispered the words “I love you.”

Jackson died on June 25 2009, at a rented Los Angeles mansion where Murray had been treating him for chronic insomnia during rehearsals for a series of 50 comeback concerts at the O2 Arena in London.

A coroner later concluded that the singer, 50, died in his bed from “acute intoxication” as a result of the anaesthetic propofol. Murray had admitted giving Jackson a small amount of propofol, a powerful surgical anaesthetic intended only for use in hospitals, but claimed it should not have been enough to kill him.

Defence lawyers claimed Jackson injected himself with an extra, lethal dose of the drug while Murray had stepped out of the room for “two minutes” to use the bathroom. But the jury of seven men and five women decided, after less than nine hours deliberation, that Murray was responsible for the singer’s death.

The doctor was portrayed by prosecutors as a substandard professional who ordered an “extraordinary” four gallons of propofol from a pharmacy, and then gave nightly doses of the drug to Jackson for two months without proper safety equipment.

At the time he noticed Jackson had stopped breathing Murray was on the phone to a cocktail waitress in Houston instead of monitoring his patient, the court heard. Murray then failed to contact emergency services for more than 20 minutes, during which time he attempted to hide vials of drugs and an IV bag which the prosecution said had been used to administer the propofol.