The Marin County Sheriff's Office says the 83-year-old man was found with a head injury Friday near Wild Iris Road and Sir Francis Drake Boulevard in the San Geronimo Valley
A friend says he saw the man hiking, but later found him on the ground severely injured.
The man was taken to the hospital where he later died.
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Investigators do not have a suspect right now, but say they've received multiple calls about a person with a gun in the area.
Officers cannot confirm if those reports and the man's death are connected.
Bay City News contributed to this report.
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