FRESNO, Calif. (KSEE/KGPE) – The Fresno County Sheriff’s Office has announced what they believe to be a connection between a recent officer-involved shooting and a homicide investigation from November.

Authorities believe 32-year-old Dennis Happawana, who was killed by sheriff’s deputies in December, is responsible for the November homicide.

On November 17, sheriff’s deputies found 44-year-old Amanda Berry dead in her front yard. Further examination showed she was shot by a 9 mm bullet.

On December 6, deputies were dispatched just three miles away from Berry’s home to respond to a shots fired call. When they arrived, Dennis Happawana was outside. Officials say he immediately fired his rifle at the deputy’s vehicle. An hours-long stand-off ensued, in which Happawana was ultimately shot and killed.

“There was no other option but for deputies to utilize lethal force,” said Sheriff-elect John Zanoni.

Inside Happawana’s home, deputies found an AR-10 rifle, a 9 mm handgun, and notebooks with anti-government messages.

“It talked about Nazis and parasites and people out to get him,” Zanoni said. “The weapons that he had were not legally purchased, were not registered to him…” he continued.

The messages found inside were similar to a note found on Berry’s property on November 17, right next to a damaged cell phone tower that they believe Happawana was drilling into.

“We believe she had gone out there because she heard the grinding because it was right outside of her residence. Surveillance footage showed she had a flashlight with her. We believe she confronted Dennis in the act of damaging the cell phone tower and at that point he fired a round from the handgun, striking her, which ended up killing her,” Zanoni said.

Zanoni said a firing test on Happawana’s 9 mm gun produced an identical strike match to the casings found at Barry’s home and Happawana’s home.

He said his family told officials he suffered from severe mental health issues.

“His parents said about three days leading up to the officer-involved shooting, they noticed his mental health declining significantly over those three days,” he said.

The family told Zanoni Happawana’s mental health declined after a major car crash about ten years ago. He was formally diagnosed with Asperger syndrome. He never elected to seek treatment or take medication.