Heather Locklear and Jack Wagner To Be Questioned Over Fight

Law enforcement sources tell TMZ ... the LAPD has prepared a file on the fight between Heather and Jack that occurred in late December at Jack's San Fernando Valley home. We're told cops were called to the home after Heather and Jack allegedly got physical with each other during a heated argument. As one law enforcement source said, "She lost it on him and he retaliated."

When cops arrived ... neither Heather nor Jack wanted to press charges ... but the file was still sent over to the City Attorney for review.

Heather and Jack now must go to an office hearing ... an informal talk in which prosecutors hear out both sides and then decide if the matter should be dropped or prosecuted. We're told the hearing will be held by the end of the month.