Los Angeles County sheriff's officials say the standoff lasted about 22 hours and finally ended at about 3:30 a.m. Friday.
City News Service says the woman in her 70s was hospitalized for unspecified medical treatment.
Authorities were called around dawn Thursday by a woman saying she needed medical assistance.
When deputies arrived at the park in Topanga Canyon, near Malibu, the woman waved a gun at them. They took cover and evacuated the area.
Authorities tried tear gas and a crisis-negotiation robot. Officials say the woman fired a gun at the robot, hit it with a broom and threw a cover over it.
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