MEDFORD, MA — Four people were seriously injured in a drunken driving crash that closed Mystic Valley Parkway for hours Thursday night, police said. Helser Msaravia, 22, of Chelsea was charged with operating under the influence. Police said he was driving a Volkswagen Jetta when he drifted into the northbound lane and crashed head-on into a BMW X3 sport utility vehicle. Two passengers in his car, a 20-year-old woman and 16-year-old, were seriously injured, while Msaravia sustained minor injuries.

A 35-year-old woman driving the BMW and her 39-year-old male passenger, both from Medford, were also seriously injured.

All five people were brought to Massachusetts General Hospital.