Police were confronted with a horrific scene. Photo / 123RF
Warning: Distressing content
A US man has been arrested after police officers responding to an emergency call in San Francisco's Bay Area discovered a truly grisly scene.
When officers arrived at the address in a quiet residential area of Ricmond, they found Dwayne Wallick, 37, allegedly eating the body of his 90-year-old grandmother, Ruby Wallick.
ABC7 news reported that police spokesman Sergeant Aaron Pomeroy revealed that Wallick was "digging in her flesh" when he was found.
Police have no clear motive for the horrific crime and investigators are reportedly probing whether drug use played any role.
Wallick and his grandmother lived at the address.
The police are expected to ask for murder charges to be filed in the case, the Mercury News reported.
The case has disturbing echoes of the 'cannibal frat boy' Austin Harrouff who murdered a Florida couple in 2016 before police found him trying to eat one his victims.
John Stevens, 59, and his wife Michelle Mishcon, 53, were killed in the attack.
Deputies had said when they arrived at the couple's home, they found the then-muscular former high school football player and wrestler in his underwear, making animal noises and biting Stevens' face as he pinned the man's body to the driveway.
He told deputies, "Help me, I ate something bad" and then admitted it was "humans" as he spat out a piece of flesh, court documents show.
Drugs were initially suspected, but an FBI toxicology report released later found that Harrouff had no hallucinogenic drugs in his system at the time of the attacks - only a trace amount of marijuana.
His trial was scheduled for May of this year, but has been postponed indefinitely.