Updated Monday at 3:30 p.m.

State and federal authorities will monitor the investigation into the death of a black man found hanging from a tree in the Southern California city of Palmdale, officials said Monday following large weekend protests.

Robert Fuller's body was found the previous Wednesday morning in Poncitlán Square in Palmdale. The 24-year-old's death was deemed a likely suicide based on preliminary findings, the Los Angeles County Sheriff's Department said.

But Fuller's family and supporters are pushing back against the department's assessment, saying his death appears to be a lynching. A growing number of residents and officials in Los Angeles County are demanding answers.

The state attorney general's office and the FBI's Civil Rights Division will oversee the investigation into Fuller's death, which is being led by the Los Angeles County sheriff's homicide bureau, Sheriff Alex Villanueva said.

The coroner's office has completed an autopsy but is awaiting toxicology results, Dr. Jonathan Lucas said. Investigators are also looking at Fuller's medical history. Homicide detectives plan to analyze the rope and its knot, canvass the area for video footage, interview Fuller's social services case worker and speak to anyone who had recently interacted with him.

They are also seeking to meet with Fuller's family, authorities said.

Fuller's death came 10 days after another black man was found hanging from a tree about 50 miles away in Victorville.

On Monday, the state Senate began its session with a moment of silence for Fuller and Malcolm Harsch. The death of Harsch, the 38-year-old black man who was found on May 31, came to light after Fuller's case. Harsch's family told the Victor Valley News on Saturday that "the explanation of suicide does not seem plausible."

Villanueva said his investigators will consult with San Bernardino detectives to see if there are any commonalities between the deaths of the two men.

Community's Call for Justice Grows

On Saturday, hundreds gathered in the park where Fuller's body was found demanding an investigation into his death. Throughout the day, protesters marched through the city's major thoroughfares and to the Palmdale's Sheriff Station.

[pullquote size="medium" align="right" citation="Diamond Alexander, Robert Fuller's sister"]'We really want to find out the truth of what really happened. It's like everything that they've been telling us has not been right.'[/pullquote]

At a rally near the tree where her brother's body was found, Fuller's sister, Diamond Alexander, expressed her skepticism that he died by suicide and said her family still had unanswered questions.

"We really want to find out the truth of what really happened," said Alexander, choking up while speaking about her brother's death. "It's like everything that they've been telling us has not been right."

Fuller's death reverberated through Palmdale and much of the region. The city is part of the Antelope Valley, a metro area that has transformed from a majority-white community into a racially diverse exurb in recent decades.

The shift has not been without tensions. Neo-Nazi groups have been reported in the area. There have also been Justice Department actions over alleged discriminatory housing and policing practices in Palmdale and the neighboring city of Lancaster.

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On Saturday, the Los Angeles County Sheriff's Department announced a virtual town hall with Palmdale and Lancaster residents for Monday.

More officials lined up behind the Fuller family's demands for answers over the weekend. The Los Angeles County supervisor for the 5th District, Kathryn Barger, asked state Attorney General Xavier Becerra to get involved in an independent investigation.

[aside tag="george-floyd" label="related coverage"]

"Your role as the lead attorney and law enforcement official for the State of California will lend additional credibility, expertise and sensitivity to an already grieving community that deserves answers," Barger wrote in a letter.

In a Facebook post Saturday, the city of Palmdale said it's "joining the family and the community's call for justice, and we do support a full investigation into his death. We will settle for nothing less than a thorough accounting of this matter."

Other city officials who had earlier echoed the county's findings seemed to join the call, including Palmdale City Manager J.J. Murphy.

"The City of Palmdale will do everything we can to assist Mr. Fuller's family during this difficult time as we all wait to learn more about his tragic death," Murphy said.

In a statement a day earlier, Murphy said the county had confirmed that Fuller had died by suicide.

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