LAPD units were called just before 2 p.m. to the Croft House furniture store in the 300 block of La Brea Avenue, near Beverly Boulevard.
LAPD Detective Herman Frettlohr said in an afternoon press conference that the victim was at the store by herself when she was attacked and killed by the suspect, who was last seen going out the back of the store, heading northbound through an alley.
The employee was found dead by a customer who entered the business, Frettlohr said.
At the press conference, police did not disclose if a weapon had been recovered.
The suspect is described as Black, wearing a black hoodie with skinny jeans and dark shoes. He had on a white N95 mask and was carrying a backpack, police said.
Video obtained by Eyewitness News shows the suspect dressed in black clothing and wearing a white face mask as he walks away from the shop.
The victim was identified as Brianna Kupfer, 24. A LinkedIn page that appears to belong to her says she was a designer at the Croft House.
It's unknown if the victim knew the suspect and a motive for the attack remains under investigation.
Police are combing through surveillance footage.