Three Mendocino County firetrucks participating in Wednesday's memorial procession for slain Sheriff's Deputy Ricky Del Fiorentino got into a fender bender collision, emergency officials said Friday.

The worst damage occurred to a South Coast Fire Protection District engine from Gualala, which was between two engines in the collision.

The impact came at about 6:40 a.m. in the dark and the rain. The firetrucks were at the end of the lengthy procession, which came to an abrupt halt on Highway 101 near the Calpella offramp.

As well as damaging the three engines, about 3,000 feet of hose spilled onto the roadway from the crumpled end of the South Coast rig.

The crash remained under investigation Friday by the CHP.

South Coast Fire Chief Gregg Warner said it appeared South Coast was rear-ended by a Redwood Coast Fire Protection District engine, pushing it into an Anderson Valley Fire Protection District engine, which narrowly missed hitting another Anderson Valley vehicle.

But it also was possible the South Coast rig first hit Anderson Valley and then was hit by the oncoming Redwood Coast engine which couldn't stop in time, Warner said.

"I'm not sure if we tapped it (the Anderson engine) or were hit by another engine from behind," Warner said.

Retired Anderson Valley Fire Chief Colin Wilson, riding with others in the Anderson engine, was taken to Ukiah Valley Medical Center for minor injuries. He was treated and released, officials said.

About 300 vehicles participated in the procession Wednesday morning, which started in Ukiah and went to Fort Bragg for a public memorial for Del Fiorentino.

The vast majority of the vehicles were law enforcement, followed by a dozen or so Mendocino County fire department vehicles.

"For the life of everybody I've talked to, nobody knows why the procession came to a complete stop on the freeway," Warner said.

The three damaged rigs are being repaired at a shop in Healdsburg, Warner said.

"We've had nothing but support from the community for this whole thing. We're hoping within a couple of months we'll have that engine back," Warner said.

(You can reach Staff Writer Randi Rossmann at 521-5412 or randi.rossmann@pressdemocrat.com.)