Four people were killed and five more were injured in four separate Bay Area crashes involving wrong-way drivers over the weekend.
Investigators suspect the wrong-way drivers in three of the crashes were under the influence of drugs or alcohol.
The California Highway Patrol said it is highly unusual to have so many wrong-way crashes in a 38-hour period.
"We know the total of wrong-way crash his account for a 10th of one percent of total crashes, an account for one percent of fatal crashes, it statistically rare," CHP Officer Ross Lee said.
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Additional coverage on the wrong-way crashes in the Bay Area:
- Woman Identified in Deadly Wrong-Way Crash on I-280 in Woodside
- Deadly Wrong-Way Crash in Sunnyvale
- Wrong-Way Driver Causes Collision on I-580 in Oakland
- 1 Dead in Wrong-Way Crash on Highway 101 in Marin County: CHP
In Sunnyvale, a 34-year-old man driving the wrong way on westbound Highway 237 Sunnyvale slammed head-on into a 22-year-old driver, CHP officers said. Both men died.
"At this point, it is suspected that the driver who was going the wrong way we suspect was under the influence of alcohol," Lee said. "It’s not confirmed yet, but that’s our suspicion right now."
On southbound Interstate 280 south of Highway 92, the driver of a sedan was driving the wrong way on southbound Interstate 280 and slammed into an SUV, killing 54-year-old Eden Palmer of San Francisco. Her 14-year-old son suffered major injuries.
CHP officers arrested 24-year-old Constellatia Martin, who was found running naked on the highway.
On Interstate 580 in Oakland, officers arrested the driver of a pickup truck for driving under the influence after he hit a city tree maintenance truck while driving the wrong way. Both drivers survived.
The spree of wrong-way crashes began in San Rafael when a 22-year-old wrong-way driver was killed after hitting another car. The other driver suffered major injuries.
The CHP said in most wrong-way driving cases, the drivers are either unfamiliar with the area of under the influence of drugs or alcohol.
