MEXICO CITY (AP) -- The arrest of a man after a woman objected to him kissing his female companion in public has prompted a "kiss-in" protest in a conservative Mexico city.

An official of the northern city of Leon says authorities are investigating police who arrested the man, identified as Manuel Berumen.

City spokesman Jesus Montano says Berumen's 12-hour arrest and 850-peso ($65 fine) fine for "insulting police" and arguing with the woman who complained appear to have been unjustified.

Montano said Monday there is no law against public kissing in Leon.

About a dozen couples gathered in the same spot Sunday for a public "kiss-in" to protest the arrest.

Known for its Catholic fervor, Leon hosted a visit by Pope Benedict XVI in March.