Chemical dependency technician Dawn Holland has accused the "Mean Girls" and "Freaky Friday" star of attacking her and spraining her arm.
Police said they are investigating the allegations and will determine whether the case should be brought to prosecutors.
However, TMZ reported Lohan is telling her friends and family Holland grabbed and pushed her, prompting her to call 911.
The actress also claims there are witnesses and surveillance-camera footage to back up her story, TMZ said Wednesday.
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