Pedro Sanchez set his bed on fire with a red disposable lighter. Then, clutching a large, jagged rock, he struck the frail, elderly people who tried to flee the deadly inferno.

“Aqui vamos a morir todos!” witnesses said Sanchez shouted as he beat a 55-year-old man in a wheelchair. “We are all going to die here.”

Though five residents of the K&K Adult Care Center in Miami escaped the Oct. 1, 2005, blaze, 78-year-old Graciela Labastilla would succumb to the toxic fumes.

In the coming days, state agents turned up evidence that the facility had failed to safeguard its elderly and disabled residents, leaving a violent man with a criminal past to prey on vulnerable adults.

Just days before he ignited the fire, Sanchez was allowed back to the home after being committed to a psychiatric ward for threatening a resident and throwing a rock into a neighbor’s house.

The Agency for Health Care Administration determined the home did not protect the residents, but no penalty was ever imposed.

In addition, Miami-Dade fire officials said the fact that hurricane shutters were fastened to the home’s windows — with no impending storms — increased the danger to the residents.

The only person charged in the death of the grandmother of 10 was Sanchez — arrested for arson and homicide — who remains in Atlantic Shores State Hospital, incompetent to stand trial.

Two weeks before the blaze, Sanchez had erupted in anger after a staff member tried to stop him from leaving the home.

The 78-year-old, who was on felony probation for carrying a concealed weapon before moving into the home, threw a rock at a neighbor’s house and threatened to hit caretakers with a stick, witnesses said.

Miami-Dade police officers finally subdued him, taking him to Palmetto General Hospital’s psychiatric ward, where he stayed for 10 days before returning to the ALF.

Over the following days, resident Omar Buttari said Sanchez repeatedly threatened “to burn the place down.”

On Oct. 1, 2005, a caretaker awoke before dawn to a wailing fire alarm. Griselda Cruz, 52, said she grabbed a fire extinguisher, but couldn’t put out the flames. Sanchez, she told detectives, was trying to keep residents from leaving by slamming their bedroom doors and screaming that everyone was going to die.

“Que has hecho?” she asked Sanchez after noticing his bed engulfed in flames. “What have you done?”

The five residents could escape only through the front and back doors because the home had not removed the aluminum shutters barricading the windows. As Cruz tried to help the elderly residents toward the front door, Sanchez struck her in the mouth with the rock. He beat Buttari on the head.

Rescue workers found Labastilla sprawled on the floor and took her to Memorial Hospital Miramar, where she died two days later of carbon monoxide toxicity.

The rock was still in Sanchez’s pocket when police confronted him down the street.

Police estimated the damage at $200,000, and K&K was shut down for good by its owner.

Family members said they were stunned to learn their mother, a retired seamstress who owned a small business in Hialeah, was living in a home with a convicted felon who had been threatening residents for days.

Under Florida law, homes are supposed to evaluate residents to determine whether they are appropriate for placement in their facilities.

“I didn’t know there was anybody like Pedro Sanchez in there,” said the victim’s son, Manny Labastilla. “If you have someone who has that type or degree of mental illness to the point where he’s going to threaten a person, he should be at a different type of facility.”