People bearing cash descended Monday on Phoenix Books in downtown San Luis Obispo to show their support for keeping locally owned shops viable.

The “cash mob” initiated by Save Our Downtown, a small citizens group that seeks to preserve the character of the downtown, was the first of its kind in the city but part of a growing phenomenon occurring across the country.

Through online social networks, people were asked to show up and spend at least $10 to show support for the business.

“We want the downtown to maintain its charm and appeal, and part of that is not just the architecture and landscape, but making sure there is a diversity of shopping options downtown,” said Allan Cooper, chairman of the group.

Cooper said the bookstore was selected by the group because many locally owned bookstores have had to close their doors in recent years.

“We are concerned that bookstores are disappearing,” he said.