NEW WESTMINSTER, British Columbia (AP) - A Canadian pig farmer confessed to killing 49 women and was caught before he could reach his goal of making it an even 50, prosecutors told jurors at the start of his murder trial yesterday.

Robert William Pickton, 56, has been charged with killing 26 women, mostly prostitutes and drug addicts who vanished from Vancouver's impoverished Downtown Eastside neighborhood in the 1990s.

Prosecutor Derrill Prevett stunned the courtroom by saying that Pickton told investigators, including an undercover officer planted in his jail cell, that he had slain 49 women.

"I was going to do one more and make it an even 50," Prevett quoted Pickton as telling investigators. "I made my own grave by being sloppy."

Pickton told one officer that he would be "nailed to the cross" and described himself as a mass murderer who deserved to be on death row, Prevett claimed.

Pickton has pleaded not guilty to six counts of first degree murder in what is expected to be the most macabre and lengthy murder trial in Canadian history. The other 20 counts are expected to be heard at a later trial. If convicted, he faces life in prison. Canada abolished the death penalty in 1976.

Defense lawyer Peter Ritchie told jurors that Pickton did not kill or participate in the murders of the six women covered in the first trial.

Ritchie asked the jury to pay close attention to Pickton's demeanor in the videotapes with his interrogators, in particular his level of sophistication. He asked the jury to listen closely to details regarding Pickton's relationship with his brother, David.

The brothers reared pigs on the family's 17-acre farm outside Vancouver, where investigators say the Picktons threw drunken raves with prostitutes and drugs. After Robert Pickton's arrest in February 2002, health officials issued a tainted meat advisory to neighbors who may have bought pork from his farm, concerned that it may have contained human remains.

David Pickton, who has not been accused in the murders, told The Associated Press in December that he intended to raise cattle on the property, now surrounded by townhouses.

Ritchie did not address Pickton's alleged murder confessions in his opening statement.

"This case will unfold slowly; this case is complicated," he said.

The first trial covers the murders of Sereena Abotsway, Mona Wilson, Andrea Joesbury, Brenda Wolfe, Georgina Papin and Marnie Frey.

Before the opening statements, British Columbia Supreme Court Justice James Williams warned the seven male and five female jurors that some of the evidence and witness testimony would be horrific.

"Some of the evidence to which you will be exposed to during the trial will be shocking and is likely to be upsetting. I must ask each of you to deal with that the best you can," he said.

Some of those shocking details came immediately.

Prevett said the government would prove that Pickton murdered six women, butchered their remains and then disposed of them. He told the jury that as a successful pig farmer, Pickton had the expertise, equipment means to dispose of the victims' remains.

The prosecution is expected to call about 240 witnesses, including relatives of the victims.

When police first went out to investigate at the farm in 2002, they found two skulls in a bucket inside a freezer in Pickton's mobile home, Prevett said.

DNA testing would later identify the skulls as those belonging to Abotsway and Joesbury, two missing sex workers from Vancouver's Downtown Eastside.

He said both skulls had wounds caused by 22-caliber bullets. He said investigators found a Smith & Wesson rifle on a shelf in the laundry room of Pickton's mobile home.