The crash was reported at about 8:05 a.m. on San Pablo Avenue near Cummings Skyway in unincorporated Contra Costa County.
Two people were airlifted to John Muir Medical Center with major injuries and a third was pronounced dead at the scene, Maguire said.
According to witness reports, a red 1988 Acura Legend was seen driving recklessly on westbound San Pablo Avenue.
A witness told officers that the Acura was weaving in and out of traffic. It passed the witness and then, for an unknown reason, crossed the double yellow lines and entered the eastbound lanes, where it was struck head-on by a 1985 Peterbilt big rig hauling two unloaded trailers, Maguire said.
The impact caused the big rig to jackknife and the Acura to spin out of control, ejecting a female passenger, Maguire said.
The driver of the big rig, 44-year-old Pittsburg resident Kishor Kumar, was airlifted to John Muir Medical Center in Walnut Creek with major injuries. He was the only person in the big rig.
The passenger who was ejected from the Acura, 44-year-old Richmond resident Geraldine Scilingo, was also airlifted to John Muir Medical Center with major injuries.
The driver of the Acura, a 59-year-old Antioch man, was pronounced dead at the scene, Maguire said.
Neither the driver nor the passenger in the Acura appeared to have been wearing seatbelts and evidence collected at the scene suggested that the driver of the Acura may have been intoxicated.
The roadway was closed while investigators and emergency personnel responded to the scene. A Sig-alert was issued at 8:25 a.m.
