The suspect in last week's gruesome murder and beheading in Santa Rosa has been found and arrested, and we now know the identity of the victim.

The head of Santa Rosa resident Elvia Lopez-Arroyo, 64, was found over the weekend on the bank of Santa Rosa Creek, as Santa Rosa police announced Monday. And as NBC Bay Area reports, the prime suspect in the case, Lopez-Arroyo's grandson, is now in police custody.

23-year-old Luis Gustavo Aroyo-Lopez was spotted on Saturday by a San Francisco police officer at the Transbay Transit Center, on the same day the victim's head was discovered. He was reportedly taken into custody without incident and transported to Sonoma County.

Santa Rosa police responded Thursday to a report of a homicide at a home on the 2500 block of Pomo Trail, and there the found the headless body of Elvia Lopez-Arroyo. On Friday, the department put out an alert that Aroyo-Lopez was at large, and was armed and dangerous.

The grandmother had reportedly been stabbed, and police found multiple weapons at the residence, as KRON4 reports.

The victim's head was then discovered Saturday morning near the Prince Memorial Greenway along Santa Rosa Creek.

It's not clear if Aroyo-Lopez had been staying with the grandmother prior to the murder. Shortly before the killing, Aroyo-Lopez had just been released from state prison and placed on Post Release Community Supervision (PRCS). He was serving time for assault with a deadly weapon and weapons possession convictions.

In a news release Monday, Santa Rosa police clarified that they had been given documentation from the family showing that Aroyo-Lopez was 23, and not 24 years old as previously stated.

He is being held without bail at the Sonoma County Main Adult Detention Facility.

The family has posted a GoFundMe to raise funeral expenses for Lopez-Arroyo, and granddaughter Maribel Moldonado writes, "She was a loving person and she adored so dearly all her grandchildren. She didn’t deserve what was done to her. Her death has impacted our family greatly and we are seeking for help during this time of despair."

Previously: Suspect Accused of Severing Santa Rosa Woman’s Head is At Large, Considered Armed and Dangerous

Photo via GoFundMe