Detectives want to know who worked on a Santa Barbara County strip mall construction project in 1979 as they seek to identify a serial killer suspected of murders and rapes in California more than 30 years ago, the Santa Barbara County Sheriff's Department said Saturday.

The office says that the "Original Night Stalker" is suspected in at least eight killings and numerous rapes that took place from 1979 to 1986 in Santa Barbara, Sacramento, Ventura and Orange counties.

Decades-old DNA evidence has linked him to the 1979 and 1981 murders of four people in Goleta, just north of Santa Barbara.

Sheriff's investigators had long suspected that the serial killer was behind the July 1981 slayings of Cheri Domingo, 35, and Gregory Sanchez, 27, while they were house-sitting in Goleta.

The slayings occurred 18 months after Dr. Robert Offerman, 44, and Alexandria Manning, 35, were killed in a Goleta condominium. Both killings occurred close to one another.

Investigators who reviewed crime reports from other law enforcement agencies have recently learned that traces of paint were found in two rapes and one homicide scene in Irvine, sheriff's spokeswoman Kelly Hoover said.

So they're looking into the possibility that the suspect may have come to the Santa Barbara area to work on a construction site, possibly as a painter.

They want to talk to anyone who worked on a strip mall construction project in Goleta around the time of the slayings. The project on Calle Real had a building permit issued to a developer from Sacramento at the beginning of 1979, Hoover said.

NOTE: An earlier version of this story included a facial composite sketch that police say is no longer accurate.

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