Alba, who was not officially named in the local police report obtained by Access Hollywood, came under investigation after several online blogs reportedly "implicated" the actress in gluing up posters of great white sharks around the city.
Photos of Alba posing in front of the posters were then posted online.
On Tuesday, the actress issued a statement to Access Hollywood, confirming she was involved in the incident and offering an apology.
"I got involved in something I should have had no part of. I realize that I should have used better judgment and I regret not thinking things through before I made a spontaneous and ill-advised decision to let myself get involved with the people behind this campaign," she said in a statement to Access. "I sincerely apologize to the citizens of Oklahoma City and to the United Way for my involvement in this incident."
According to the police department's crime report, the shark posters were discovered on at least two electrical boxes by Wendell Whisenhunt of the Parks and Recreation Department of Oklahoma City.
The shark posters were glued to the side of an underpass and on top of a United Way billboard.
According to a blog from "White Mike," the posters are being put up to draw attention to the Great White Shark population.
And on June 4, White Mike wrote, " Just came back from OK! Had a blast tagging with a new friend. Check out the pics with Jessica Alba's help here" on his Twitter account, however, the link to the reported images has been removed.
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