Dylan Schwarz, 32, and Aidan McWhinney, 30, likely died as a result of "illicit substance utilization," the sheriff said.
Hazmat crews responded to the Sleepy Hollow neighborhood after the initial first responders reported a possible hazardous materials incident related to the death.
Greg Lee reports from San Anselmo.
The illegal skimming device was found by a Marin County weights and measures inspector at the Gas & Shop gas station on Sir Francis Drake Boulevard earlier this December, county officials said.
The warning comes after a credit card skimming device was discovered at a gas station earlier this month.
A deer in San Anselmo got in on the festive holiday spirit. It all happened by accident when the buck's antlers got tangled in Christmas lights last week.