Driver accused of ramming bicyclist in Marin County

Mark Rafferty was arrested on suspicion of assault with a deadly weapon after hitting a bicyclist with his car on Point Reyes-Petaluma Road west of Nicasio Valley Road on Monday. Mark Rafferty was arrested on suspicion of assault with a deadly weapon after hitting a bicyclist with his car on Point Reyes-Petaluma Road west of Nicasio Valley Road on Monday. Photo: Google Maps Photo: Google Maps Image 1 of / 3 Caption Close Driver accused of ramming bicyclist in Marin County 1 / 3 Back to Gallery

A 62-year-old Bolinas man has been arrested in an apparent case of road rage, accused of ramming a bicyclist from behind with his car in Marin County, officials said Tuesday.

Mark Rafferty, the driver, was arrested Monday on suspicion of assault with a deadly weapon following the angry encounter with bicyclist Charles Keane-Zirepolo, 25, of San Francisco, said Officer Andrew Barclay, a spokesman for the California Highway Patrol.

Rafferty was driving east about 1 p.m. on Point Reyes-Petaluma Road in unincorporated Marin County when a bicyclist in front of him drifted into his lane to snap a photo of a bicycling pal who was on the shoulder, Barclay said. Rafferty honked at the rider in his way and tried to pass the cyclists by crossing into the westbound lane, he said.

But as the driver was about to pass, Keane-Zirepolo, became startled and veered left and across the lanes, causing Rafferty to slam on his brakes to avoid a crash, according to Barclay.

“Rafferty proceeded to drive ahead and pull to the right shoulder where he exited his vehicle and yelled at Keane-Zirepolo to come to his location so he could express his disapproval for how he was riding,” he said.

Keane-Zirepolo, however, “displayed an obscene hand gesture” as he rode past the yelling Rafferty, Barclay said.

The motorist allegedly jumped back in his car and drove after Keane-Zirepolo, striking the back of his bicycle, crushing his rear tire and causing “him to be ejected from the bicycle onto a dirt hill side,” he said.

Rafferty continued eastbound until he could turn around and went back to the scene, Barclay said. Keane-Zirepolo declined medical treatment from paramedics called to the scene, Barclay said.

Hamed Aleaziz is a San Francisco Chronicle staff writer. E-mail: haleaziz@sfchronicle.com Twitter: @haleaziz