SANTA ANA, Calif. (AP) - Five family members whose decomposed bodies were found in an oceanside home in Orange County earlier this year apparently made a suicide pact, a sheriff's department spokesman said Wednesday.

Investigators concluded that Manas Ucar, a 58-year-old mechanical engineer and expert trial witness, was shot to death by his wife Margrit, who then turned the gun on herself, sheriff's spokesman Jim Amormino said.

The couple's twin 21-year old daughters and their grandmother, whose bodies were also found in the upscale home in San Clemente, died of prescription drug overdoses. Ucar had a lethal dose of Vicodin in his system before he was shot in the chest.

"We believe it was a suicide pact and maybe he didn't die soon enough," Amormino said. "He would have died if she didn't shoot him."

Investigators reached the conclusion after receiving a report from the coroner's office, Amormino said. He said he did not know the reasons for the suicides.

The bodies of the Turkish-American family were found clad in black clothing in May in a gated community about 65 miles southeast of Los Angeles. Relatives had forced their way into the house after not hearing from the family.

The couple's bodies were found in a downstairs closet with two handguns nearby. Twins Margo and Grace and their 72-year old maternal grandmother, Fransuhi Kesisoglu, were found dead in an attached bedroom.