A handgun once owned by Christopher Dorner is being auctioned online by a Las Vegas pawn shop owner. Dorner, the former police officer charged in a series of shooting attacks on Los Angeles Police Department officers and their families in February, sold the .38 revolver to the pawn shop for $50 two weeks before setting off on a rampage, according to the pawn shop owner who spoke to Las Vegas ABC station KTNV.

The shooting spree eventually left four people dead, including two Los Angeles police officers. Three other police officers were wounded.

Christopher Dorner's .38 revolver in Las Vegas

The two-week auction has so far had more than 39 bidders who have driven up the price of the Astra model 960 revolver to more than $2,000. The pawn shop, Bargain Pawn, said proceeds from the sale would go to charity.

"The coward and murderer Christopher Dorner frequented many gun shops in Las Vegas and sold us this revolver on January 15, 2013," the sale posting says. "We were visited by local police and turned over the video surveillance we had."

Dorner kept a residence in Las Vegas, and that home was part of the police investigation into his whereabouts.

The pawn shop owner, George Bramlett, had hoped to donate proceeds from the sale of the gun to the families of the police officers allegedly killed by Dorner. But he told KTNV that the families were not interested.

Not everyone is happy about the gun sale.

A group raising funds for a fallen officer told the Los Angeles Times that money raised by the sale of the gun wasn't welcome. Sgt. Brian Smith, president of the Riverside Police Officers Association, described the gun sale as "tasteless," the Times reported.

"We're not interested in the money," Smith told the paper. The union is raising funds to benefit the children of Officer Michael Crain, who was one of Dorner's alleged victims. Smith suggested that the pawn shop should turn the gun into local police to have it destroyed, the Times reported.

Dorner was the subject of an intense manhunt following the shooting deaths of four people, including two police officers and the daughter of another. He died during a standoff with police at a cabin in Big Bear, Calif.

An autopsy revealed that Dorner died from a single gunshot wound to the head.