Louisiana Revised Statutes Tit. 40, § 580.4. Complaints or orders; service; posting

A. Complaints or orders issued by a public officer pursuant to an ordinance adopted under this Part shall be served upon persons either personally or by registered mail. If the whereabouts of the persons are unknown and cannot be ascertained by the public officer by the use of reasonable diligence and the public officer makes an affidavit to that effect, the complaint or order may be served by publication once each week for two successive weeks in a newspaper printed and published in the municipality, or, in the absence of such a newspaper, in one printed and published in the parish and circulating in the municipality in which the dwellings are located.

B. A copy of the complaint or order shall be posted in a conspicuous place on the premises affected by the complaint or order. A copy shall also be filed in the mortgage office of the parish in which the dwelling is located. This filing of the complaint has the same force and effect as the filing of lis pendens notices.