The pilot of a Cal Fire air tanker mistakenly dropped fire retardant on a neighborhood in Windsor, where there was no fire, and left a big, pink mess.

The air tanker was carrying 1,000 gallons of the retardant Thursday as it flew over the neighborhood. About 100 gallons dropped on the Decantor Circle yards, sidewalks and parked vehicles below.

Resident Alex Cruz and his neighbors regularly see air tankers filled with fire retardant flying in to land at the Sonoma County Airport. On Thursday, they got a close-up look at the material.

"I came outside everything was pink," Cruz said. "I've never seen this before."

Cal Fire crews broke out their fire hoses to clean up the mess Thursday. The agency said a pilot returning from a fire in Penngrove accidentally made the drop before touching down at the airport, coating nine houses, 12 cars, a camper, landscaping and the street.

"We got the heavy part of it," Cruz said. "Looks like they stopped; probably noticed they did something wrong."

Cal Fire said the pink stuff is a mixture of water, fire retardant, dye and fertilizer. The agency said it is not toxic to fish and wildlife.

City crews came out to cover storm drains and pump the water into trucks as firefighters sprayed streets and sidewalks and scrubbed cars that could be damaged.

"It's slippery when wet," said Ben Nicholls of Cal Fire. "It's a slip hazard, has a reaction with automotive paint if its left on it, will create issues with the paint."

Cruz's daughter's car was scrubbed, but some pink spots remained. The family has called their insurance company.

Cal Fire said the remaining pink residue will dissipate over time. The incident is under investigation.