A senior editor for PC World Magazine was fatally shot in his California home in what authorities said Wednesday was a drug-related attack.

Rex Farrance, 59, the San Francisco-based magazine's senior technical editor, was shot in the chest after four masked men broke into his home Tuesday evening, Pittsburg police said Wednesday.

The assailants also pistol-whipped Farrance's wife, Lenore Vantosh-Farrance, 56, a registered nurse. She called authorities, but the attackers fled before officers arrived. No one has been arrested, officials said.

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"We have substantial reason to believe that the victim and his wife were involved in the possession and, potentially, the distribution of illegal narcotics," said Pittsburg police Inspector John Conaty, who declined to specify what type of drugs were involved.

The couple's son, Sterling Farrance, 19, blasted the police assertion that they were involved with illegal drugs, saying he grew and stored medical marijuana at the home with his parents' permission.

"I have a prescription. I'm a patient. It was medical," Sterling Farrance told the San Francisco Chronicle. "This one officer I remember at the house, he had this predisposition to think it was all illegal."

Colleagues at PC World described Farrance as a fitness buff, rock-music fan and a dedicated husband and father who excelled at his job.

"We're all in shock here," said Denny Arar, a PC World senior editor. "Rex loved his work. He really cared about covering technology in a way that was useful for readers. He cared a lot about people, period, including his co-workers."