Denise Richards Struck Fear in Aaron Phypers' Parents, 911 Audio Reveals

Denise Richards struck fear into the hearts of Aaron Phypers' elderly parents when she showed up at their home to get some dogs ... at least according to the 911 call from the latest divorce drama.

TMZ obtained the dispatch audio from Sunday's incident at the Calabasas home Aaron shares with his parents and brother ... and you hear the dispatcher relay that Aaron feared for his parents.

We broke the story ... sources close to Aaron claim his estranged wife showed up at the home unannounced and started banging on a back door, demanding to be let inside.

Aaron left because Denise has a restraining order against him, and we're told his parents opened the door for her ... only for her to barge in, demand the dogs, scream at them, put her finger in their faces, and allegedly get into it with Aaron's brother.

Photos show Denise talking to sheriff's deputies in the driveway ... and there's also a shot of Aaron consoling his frail mother.

Denise's divorce lawyer told us she didn't violate the restraining order, confirmed Aaron wasn't there before entering, and only went to retrieve the dogs after learning Aaron put one down without her knowledge or permission.