MARTINEZ (BCN/CBS SF) — A man killed Wednesday afternoon in a solo vehicle crash on state Highway 4 in Martinez has been identified as 33-year-old John Thomas of San Francisco, the Contra Costa County coroner’s office said Thursday morning.

The coroner ID’d the man as 33-year-old San Francisco resident John Thomas.

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Thomas was driving a 1999 Lexus headed west on Highway 4 at about 4 p.m. Wednesday just east of the Alhambra Avenue off-ramp when the car veered off the roadway and hit a tree, according to the California Highway Patrol.

The identity of a 53-year-old man killed in a second crash in that same area about four hours later has not been released as of Thursday morning, a coroner’s office spokesman said.

That solo wreck happened around 8:10 p.m. Wednesday when that vehicle — also a Lexus — went off the south side of eastbound Highway 4 just west of Alhambra Avenue and overturned, ejecting the driver.

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That man was taken to John Muir Medical Center in Walnut Creek, where he was pronounced dead a short time later, the CHP said.

The two crashes brought the number of fatal solo vehicle accidents on Highway 4 up to three for the week. On Monday morning shortly before 8 a.m., Contra Costa CHP was advised of a solo overturned vehicle crash on eastbound Highway 4, just east of Loveridge Road.

Arriving emergency personnel and CHP determined that a solo black Nissan Ultima had overturned along the right shoulder area and the driver had been ejected from the Nissan and sustained fatal injuries. He was identified as a 41-year-old male from Sacramento.

The CHP is investigating all three crashes. Anyone with information about them is asked to contact the Contra Costa-area CHP office at (925) 646-4980.

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