STOCKTON (CBS13) — The suspect accused of shooting and killing a veteran firefighter made his first court appearance.

Inside a San Joaquin Superior courtroom, a judge formally charged Robert Somerville, 67, with one count of murder and one count of intentional discharge of a firearm resulting in death. 

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The defendant appeared somber yet fidgety at times while scanning the room. His family members watched the proceeding while he could see Stockton officers, too.

Cpt. Vidal “Max” Fortuna responded to a dumpster fire when police say Somerville shot at him early Monday morning. 

But the accused shooter’s family say Somerville mistook the veteran firefighter for an intruder and announced he was armed. 

“It was a case of mistaken identity,” said Greg Somerville, the suspect’s brother. “He thought he was protecting himself and he had a fear for his life.” 

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Somerville claims his business and home in the warehouse had been a target for several attempted break-ins in the past.

Firefighters initially responded to the dumpster fire but saw flames encroaching on a nearby warehouse.

Since Fortuna’s death, there has been an outpour of tributes and condolences for the fallen firefighter. People who knew the 47-year-old say he had a positive outlook. Whether in uniform or not, he always did something to help others.

He leaves behind a wife and two adult children.

The lead prosecutor is vowing to seek justice for Fortuna’s loved ones and work family.

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“My job is two-part: to ensure public safety and those who commit the crime are held accountable,” said Tori Verber Salazar, district attorney of San Joaquin County. “But it’s also healing.”