A father is in custody, accused of attempting to sacrifice his own son in a San Diego area cemetery.

Joseph Ramirez, 30, took his family to Mount Hope Cemetery Saturday around 4:30 p.m. and told them his dead grandmother told him to sacrifice the 8-year-old boy, according to San Diego police.

Officers released a report stating Ramirez had brought candles to the cemetery. One of the candles broke, and he used a piece of the broken glass to slash open his son's forearms.

Ramirez then slashed his own forearms.

Medical assistant Corey Granberry witnessed the incident and jumped in to help along with her best friend Jaymisha Pires.

Granberry was visiting her godson's grave when she saw a woman, clothes covered in blood, calling for help.

“Out of all these people were passing her by, she almost got hit by a car, all these people that were just passing her by," Granberry said.

She said somehow Pires was able to convince Ramirez to let the child go.

Granberry's medical training kicked in.

“I grabbed the little boy sat him down on the curb grabbed a shirt and wrapped it up on his arm,” she said.

When officers arrived, they transported Ramirez to a nearby hospital for treatment. Once he's released, officers say Ramirez will be booked into county jail on charges of child abuse and assault with a deadly weapon.

The boy was taken to Rady Children's Hospital for treatment.

Granberry said she was inspired earlier in the week by a group of construction workers who jumped in to help a family injured in a rollover crash.

“I think sometimes people are put in places. And honestly, we were at the right place at the right time,” she said.

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