Grenier, who has previously romanced actress Isabel Lucas, is alleged to be enamored by Greene after meeting her at a surfing event in Santa Barbara, California, over the weekend.
A source tells the New York Post's gossip column Page Six, "Once they met, they were inseparable all weekend. By Sunday night, they were on the dance floor together."
But the Learn to Ride surf camp wasn't without incident -- Grenier was reportedly involved in a confrontation with police after locals complained that the celebrity event, which also featured Good Charlotte rockers Benji and Joel Madden, was causing too much commotion.
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