LOS ANGELES (Reuters) - Atlantic City's eleven casinos saw a 17.9 percent decline in second-quarter gross operating profit, according to the New Jersey Casino Control Commission.

Gross operating profit totaled $291.3 million during the quarter, down from $354.9 million in the year-ago quarter.

Gross operating profit represents earnings before interest, taxes, depreciation, amortisation and charges from affiliates. When all of those items are included in results, the industry's second-quarter net profit was $65 million, down by more than one-third from a year earlier.

Net revenues fell by 2.9 percent for the period to $1.19 billion.

Including results from the Sands Hotel Casino, which closed last November, gross operating profit posted a 19 percent drop on a 6.1 percent decline in net revenue.

Atlantic City casinos have suffered from competition with new slot machine gambling facilities opened in nearby Pennsylvania and New York.

The 11 Atlantic City properties include Borgata Hotel Casino & Spa, a joint venture of MGM Mirage and Boyd Gaming Corp. ; Harrah's Entertainment Inc.'s Harrah's Marina; and Trump Entertainment Inc.'s three properties.