Late Thursday, Petaluma police said the man had suffered an apparent gunshot wound to his chest.
Other information remained sketchy Thursday, with authorities withholding numerous key details, including whether the man was armed when he appeared at the trailer door, where deputies "engaged the suspect with their weapons," according to sheriff's officials.
Officers at the scene on Hoff Road had credible information the man was armed and had been involved in violence, authorities said.
Stapleton said he could not release some information because detectives were still determining what happened.
"It was a very complex event. It's going to take us some time ... before we can articulate the precise sequence of events," Stapleton said.
Meanwhile, a man who was with Garcia at the outset of the nearly 20-hour standoff described the initial moments, including his escape from the trailer where, he said, he saw Garcia pull a black rifle from a duffel bag.
Outside, the 43-year-old handyman — who gave only his first name, Victor — encountered a large contingent of heavily armed officers.
"He looked normal," Victor said of Garcia. He said he knew the man's girlfriend, who became a hostage during the standoff before she was let out of the trailer more than 10 hours into the ordeal. "He didn't look like a drug addict or anything like that," Victor said. "I never thought something like that would happen."
Garcia, who also went by the name Marron Garcia according to court records, was wanted on a $150,000 warrant stemming from an arrest in February by Napa police. He had illegal weapons, ammunition and methamphetamine at his Napa home where his two young children lived, Napa police Lt. Gary Pitkin said.
Pitkin and a team of Napa County officers went looking for him, following Garcia's cellphone signal. The trail took them Tuesday to Sonoma Valley and a 5th-wheel vacation trailer parked on property on a bucolic lane in western Kenwood.
Pitkin said Napa officers arrived at about noon and, after surveying the situation, asked the Sonoma County sheriff's SWAT team for help.
During the standoff Garcia talked periodically to a variety of law enforcement negotiators attempting to get him to surrender peacefully.
During their talks, the man claimed to have killed someone and committed other violent felonies, according to sheriff's Lt. Bret Sackett, the Sonoma police chief. The man then became despondent and talked of getting officers to shoot him before he cut off communication.
After about 6 p.m. Wednesday, in an attempt to get him talking again, deputies fired tear gas into the trailer and set off flash-bang blasts, sheriff's officials said.
"It abruptly changed," Stapleton said. "Law enforcement faced a situation that was tense, uncertain and rapidly evolving."
Garcia reportedly responded by shooting a gun multiple times out into the yard. The shots hit at least two law enforcement vehicles and a nearby home, officials said.
Deputies returned fire, according to Stapleton.
More tear gas was fired into the trailer, resulting in the man opening the front door. When the man appeared, deputies fired, Sackett said.
On Wednesday night, Sackett said it was possible the man was holding an assault rifle, but a news release Thursday from the Sonoma County Sheriff's Office did not mention whether he was armed at the door.