As the Nuns Fire edges closer to one of Napa's most iconic wineries, a firefighter has lost his life in the process of trying to keep the fire at bay. The fireman's vehicle, a water tanker, veered off the steep and windy Oakville Grade road around 7 a.m. Monday, flipping over and killing him in the process, as the Chronicle reports. The tanker was headed to battle the fire now threatening Robert Mondavi winery, on Highway 29.

The accident happened on the road that connects Napa Valley to Sonoma Valley, west of Highway 29, and the water tanker appears to have gone out of control while headed downhill, east, toward Napa.

The firefighter killed was a contract firefighter, as ABC 7 reports. "Somewhere on this steep road something happened, he lost control and the water tender rolled in an upside-down position down the grade," says a Cal Fire official to the station.

The Nuns Fire, which began last Sunday near Nuns Canyon Road in Glen Ellen, has been burning on the Napa side of the ridge for about a week, but has been mostly kept away from the grapevine-filled valley floor. The fire is now 50 percent contained.

The firefighter has not yet been publicly identified.

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