A convicted sex offender charged with killing an elderly woman and hiding her body in his trunk lived less than two miles away from the victim, who disappeared shortly after returning home from volunteering.

Timothy Mackley, 58, appeared in a Portland court Wednesday — nearly a week after she went missing — and pleaded not guilty to murdering 89-year-old Marcine Herinck. He also waived his right to a probable cause hearing.

Mackley is a convicted sex offender who has a criminal history in Washington state and Oregon in the 1980s. He pleaded guilty to sexual abuse and sodomy in Multnomah County and was sentenced to prison in 1989, court records show.

He was arrested in 2009 for failing to register as a sex offender.

SOUTH CAROLINA MAN LINKED TO 2 KIDNAPPINGS, 1 SEX ASSAULT, POLICE SAY

Court records show Mackley told officers in Oregon he has been diagnosed with schizophrenia and bipolar disorder and lives on disability payments of less than $1,000 a month. He said in his spare time he volunteers driving people to Alcohol Anonymous meetings.

Family members told FOX12 earlier this week Herinck was last seen on the night of Sept. 18.

“She had pie and coffee in the microwave,” her granddaughter-in-law, Julie Herinck, said. “The microwave was still beeping in the early hours of Wednesday morning when the family arrived, and we realized she wasn’t there.”

The elderly woman’s garage door was open and her keys, phone and purse were still in the house.

Search and rescue crews spent days looking for her — making repeated pleas to the public for tips — until police on Monday developed new information that suggested foul play and pointed them in Mackley's direction, Portland police Sgt. Christopher Burley said.

“[Herinck] put such a legacy in their family. She literally gave them so much joy,” family friend Bobbi Anderson told FOX12.

The Associated Press contributed to this report.