Petaluma police cleared a large homeless encampment on the west bank of the river Thursday.

More than 40 cubic yards of waste — about 12 pickup truck loads — were hauled off from the illegal encampment, the Petaluma Police Department reported. They also dismantled a 10-foot-by-10-foot structure.

The Sonoma County Water Agency, Conservation Corps and Mary Isaak Center assisted the police department’s Homeless Outreach Services Team in the cleanup. It took 27 people to clear the camp, where police said they also found hidden drugs and hypodermic needles.

Mary Isaak Center outreach services workers were on scene to offer support and resources to the homeless, but no one was found at the camp. Police said they previously visited the site and posted a notice days before clearing the illegal camp.

You can reach Staff Writer Eloísa Ruano González at 707-521-5458 or eloisa.gonzalez@pressdemocrat.com. On Twitter @eloisanews.