SAN FRANCISCO (KGO) -- The National Park Service police have added extra patrols at San Francisco's Fort Mason this weekend to keep people from trashing the area.
The move comes after piles of trash were left strewn across the park during the warm weekend weather last month.
When word of this mess got out, several volunteers helped pick up the trash.
The city spends about $400,000 a year cleaning up after weekend crowds at local parks. Residents say people not picking up their trash is a growing problem.
Park police in SF on lookout for 'trashers'