EDITOR’S NOTE: This story has been updated with a response from El Super management.

Local 770 of the United Food & Commercial Workers International Union on Wednesday said that members working for the El Super supermarket chain have voted to authorize a strike if contract negotiations break down.

The union’s contract with the Paramount-based bargain chain, which has supermarkets in California, Arizona and Nevada, expired in September. Mexican supermarket giant Grupo Comercial Chedraui owns more than 80 percent of El Super, owned by Bodega Latina Corp. The company operates 14 stores in Los Angeles County, according to its web site.

The union said Friday’s vote followed a complaint to the National Labor Relations Board about alleged harassment of workers and anti-union activities by El Super management in recent months.

In a statement late Wednesday, El Super noted that a group of its employee not supportive of the union had themselves filed unfair labor practice charges with the NLRB, alleging that the UFCW representatives “coerced and intimidated employees by threatening and insulting them both physically and verbally” prior to Friday’s contract vote. It also said that some employees last month had filed a petition with the NLRB to decertify the union.

“El Super is disappointed that the UFCW, which represents employees at 7 of our 46 stores, has rejected our best and final offer, as it contained wage increases for all employees over the next five years, up to four days of additional paid time off, and a guaranteed number of weekends off for tenured employees, among other benefits,” the company said in a statement.