SAN JOSE (KPIX) — Authorities cleared out a massive cache of weapons, ammunition and over a dozen Molotov cocktails from the home of VTA shooter Samuel Cassidy on Friday afternoon, finally reopening the neighborhood for area residents.

On Friday, investigators revealed that Cassidy started the fire at the home by leaving rounds of ammunition slow-cooking in a pot on his stove.

“The ammunition in that pot would have heated to a point where the powders inside would have detonated and ignited the accelerants that were placed in the kitchen, causing that residence to catch fire,” explained Santa Clara County Sheriff Sgt. Joseph Piazza.

Among the items found by authorities investigating the house on Angmar Court in East San Jose were a dozen weapons, 17 Molotov cocktails and approximately 25,000 rounds of ammunition of various calibers, according to the Santa Clara County Sheriff’s Office.

KPIX reporter Len Ramirez tweeted some of the photos of the seized arsenal provided by the sheriff’s office.

“We’ve been removing ammunition from the residence for the past two days. The new estimate is roughly 25,000 rounds of ammunition in various calibers,” said Piazza.

Shortly after 2 p.m. Friday, investigators had left the scene and neighbors who lived within a block of the house were finally allowed to return home for the first time since Wednesday afternoon.

Police had evacuated the entire cul de sac where Cassidy lived plus two houses on the back side.

Neighbors were eager to get back home after three days and grateful that there was no more loss of life.

“I never expected him to have all that stuff inside,” said neighbor Doug Suh.

Earlier Friday, bomb squad personnel detonated a suspicious device authorities discovered, according to authorities.

At the time, there was still a significant San Jose police and fire presence on Angmar Court, as well as the bomb squad from the Santa Clara County Sheriff’s office.

KPIX 5 reporter Justin Andrews posted photos from the scene shortly after authorities said that the device was found. It was detonated shortly after noon to ensure the safety of area residents.

Police blew it up, but it turned out it was only a discarded box of batteries and wires.

The multi-day investigation at Cassidy’s home comes after new details emerged about what may have set him off.

“We know that he killed nine people. I have no reason to believe he would’ve stopped there, perhaps, if we hadn’t been there. We will probably never know,” said Santa Clara County Sheriff Laurie Smith.

Chilling surveillance video was released Thursday showing Cassidy walking in the railyard between the two buildings where the shootings took place Wednesday morning.

The Wednesday morning fire was reported around the same time the first calls came in for the shooting as Cassidy began his deadly rampage at the VTA rail yard. San Jose Fire crews responded to the two-alarm fire at around 6:40 a.m., not knowing they were connected at the time.

At around 1 p.m. Wednesday afternoon, KPIX 5 cameras were asked to move away from the home for personal safety as the Santa Clara County Sheriff’s Office bomb squad set up a block safety radius around the home.

Officials later confirmed that cans of gasoline and hundreds of rounds of ammunition had been found inside the home. Authorities described some of the items as “bomb-making materials.”

On Thursday, neighbors who live nearby were still in shock and disbelief.

“What the hell? That’s crazy. Just right across the street too, you know? You never know,” said area resident Nima Agago.

When asked what kind of person would do such things, Agago replied, “Nasty, you know? Glad to hear he’s not here, you know? I don’t feel that anyone should die, but if you’re out here killing like eight people and are going to blow up other people’s houses? It’s probably better for the community that you’re no longer here.”