AMHERST, Mass. (AP) -- Thousands of supporters demanding that marijuana be legalized have descended on Amherst for an annual rally.

The Amherst Common was the site of the 22nd annual Extravaganja on Saturday. It was hosted by the University of Massachusetts Amherst Cannabis Reform Coalition.

The Daily Hampshire Gazette reported ( ) that one arrest was made. Police did not release details on charges or the identity of the person arrested.

Organizers said an estimated 5,000 to 6,000 people attended the six-hour rally and music festival.

Police Chief Scott Livingstone said traffic is usually more of a concern than the behavior of the crowd. For the past four years, possession of an ounce or less of marijuana is a civil violation in Massachusetts.